Merge pull request #2 from giann/feature/lex-parse

Lexing & Parsing

34 files changed, 4335 insertions, 210 deletions

diff --git a/.jshintrc b/.jshintrc
new file mode 100644
index 0000000..e64eb7e
--- /dev/null
+++ b/.jshintrc
@@ -0,0 +1,6 @@
+{
+    "node": true,
+    "esversion": 6,
+    "indent": false,
+    "white": false
+}
\ No newline at end of file
diff --git a/README.md b/README.md
index 8468a25..837e792 100644
--- a/README.md
+++ b/README.md
@@ -201,6 +201,7 @@
 - [ ] Standard library
     - [ ] Base lib
         - [x] ...
+        - [ ] require
         - [ ] dofile
         - [ ] loadfile
         - [ ] load
diff --git a/src/lapi.js b/src/lapi.js
index d0c099f..36da7c6 100644
--- a/src/lapi.js
+++ b/src/lapi.js
@@ -1,18 +1,18 @@
-/* jshint esversion: 6 */
 "use strict";
 
 const assert    = require('assert');
 
+const ldebug    = require('./ldebug.js');
 const ldo       = require('./ldo.js');
+const lfunc     = require('./lfunc.js');
+const llex      = require('./llex.js');
 const lobject   = require('./lobject.js');
+const lstate    = require('./lstate.js');
 const ltm       = require('./ltm.js');
-const lfunc     = require('./lfunc.js');
 const lua       = require('./lua.js');
 const luaconf   = require('./luaconf.js');
-const lstate    = require('./lstate.js');
-const lvm       = require('./lvm.js');
 const lundump   = require('./lundump.js');
-const ldebug    = require('./ldebug.js');
+const lvm       = require('./lvm.js');
 const MAXUPVAL  = lfunc.MAXUPVAL;
 const CT        = lua.constant_types;
 const TS        = lua.thread_status;
@@ -138,7 +138,7 @@ const lua_settop = function(L, idx) {
 
 const lua_pop = function(L, n) {
     lua_settop(L, -n - 1);
-}
+};
 
 const reverse = function(L, from, to) {
     for (; from < to; from++, to--) {
@@ -150,7 +150,7 @@ const reverse = function(L, from, to) {
 
 /*
 ** Let x = AB, where A is a prefix of length 'n'. Then,
-** rotate x n == BA. But BA == (A^r . B^r)^r.
+** rotate x n === BA. But BA === (A^r . B^r)^r.
 */
 const lua_rotate = function(L, idx, n) {
     let t = L.stack[L.top - 1];
@@ -357,7 +357,7 @@ const lua_settable = function(L, idx) {
 };
 
 const lua_setfield = function(L, idx, k) {
-    auxsetstr(L, index2addr(L, idx), k)
+    auxsetstr(L, index2addr(L, idx), k);
 };
 
 const lua_seti = function(L, idx, n) {
@@ -515,11 +515,11 @@ const lua_rawlen = function(L, idx) {
 };
 
 const lua_tointeger = function(L, idx) {
-    return lvm.tointeger(index2addr(L, idx))
+    return lvm.tointeger(index2addr(L, idx));
 };
 
 const lua_tonumber = function(L, idx) {
-    return lvm.tonumber(index2addr(L, idx))
+    return lvm.tonumber(index2addr(L, idx));
 };
 
 const lua_tothread = function(L, idx) {
@@ -587,7 +587,7 @@ const f_call = function(L, ud) {
 
 const lua_type = function(L, idx) {
     let o = index2addr(L, idx);
-    return o.ttnov(); // TODO: isvalid ? luaO_nilobject != nil tvalue ?
+    return o.ttnov(); // TODO: isvalid ? luaO_nilobject !== nil tvalue ?
 };
 
 const lua_typename = function(L, t) {
@@ -597,7 +597,7 @@ const lua_typename = function(L, t) {
 
 const lua_isnoneornil = function(L, n) {
     return lua_type(L, n) <= 0;
-}
+};
 
 const lua_istable = function(L, idx) {
     return index2addr(L, idx).ttistable();
@@ -626,13 +626,14 @@ const lua_rawequal = function(L, index1, index2) {
 ** 'load' and 'call' functions (run Lua code)
 */
 
-const lua_load = function(L, data, chunckname) {
+// TODO: reader is ignored because we don't implement ZIO
+const lua_load = function(L, reader, data, chunckname, mode) {
+    let z = new llex.MBuffer(data);
     if (!chunckname) chunckname = "?";
-    
-    let status = ldo.luaD_protectedparser(L, data, chunckname);
-    if (status === TS.LUA_OK) {
+    let status = ldo.luaD_protectedparser(L, z, chunckname, mode);
+    if (status === TS.LUA_OK) {  /* no errors? */
         let f = L.stack[L.top - 1]; /* get newly created function */
-        if (f.nupvalues >= 1) { /* does it have an upvalue? */
+        if (f.nupvalues >= 1) {  /* does it have an upvalue? */
             /* get global table from registry */
             let reg = L.l_G.l_registry;
             let gt = reg.value.get(lua.LUA_RIDX_GLOBALS - 1);
@@ -640,7 +641,6 @@ const lua_load = function(L, data, chunckname) {
             f.upvals[0].u.value = gt;
         }
     }
-
     return status;
 };
 
@@ -663,7 +663,7 @@ const lua_callk = function(L, nargs, nresults, ctx, k) {
         ldo.luaD_callnoyield(L, func, nresults);
     }
 
-    if (nresults == lua.LUA_MULTRET && L.ci.top < L.top)
+    if (nresults === lua.LUA_MULTRET && L.ci.top < L.top)
         L.ci.top = L.top;
 };
 
@@ -714,7 +714,7 @@ const lua_pcallk = function(L, nargs, nresults, errfunc, ctx, k) {
         status = TS.LUA_OK;
     }
 
-    if (nresults == lua.LUA_MULTRET && L.ci.top < L.top)
+    if (nresults === lua.LUA_MULTRET && L.ci.top < L.top)
         L.ci.top = L.top;
 
     return status;
diff --git a/src/lbaselib.js b/src/lbaselib.js
index 012f5c3..77638d0 100644
--- a/src/lbaselib.js
+++ b/src/lbaselib.js
@@ -1,4 +1,3 @@
-/* jshint esversion: 6 */
 "use strict";
 
 const assert  = require('assert');
@@ -91,7 +90,7 @@ const luaB_rawset = function(L) {
 
 const luaB_type = function(L) {
     let t = lapi.lua_type(L, 1);
-    lauxlib.luaL_argcheck(L, t != CT.LUA_TNONE, 1, "value expected");
+    lauxlib.luaL_argcheck(L, t !== CT.LUA_TNONE, 1, "value expected");
     lapi.lua_pushstring(L, lapi.lua_typename(L, t));
     return 1;
 };
diff --git a/src/lcode.js b/src/lcode.js
new file mode 100644
index 0000000..d8b0252
--- /dev/null
+++ b/src/lcode.js
@@ -0,0 +1,1266 @@
+"use strict";
+
+const assert   = require('assert');
+
+const llex     = require('./llex.js');
+const llimit   = require('./llimit.js');
+const lobject  = require('./lobject.js');
+const lopcode  = require('./lopcodes.js');
+const lparser  = require('./lparser.js');
+const ltm      = require('./ltm.js');
+const lua      = require('./lua.js');
+const lvm      = require('./lvm.js');
+const CT       = lua.CT;
+const OpCodesI = lopcode.OpCodesI;
+const TValue   = lobject.TValue;
+
+const luaO_arith = function(L, op, p1, p2, res) {
+    switch (op) {
+        case lvm.LUA_OPBAND: case lvm.LUA_OPBOR: case lvm.LUA_OPBXOR:
+        case lvm.LUA_OPSHL: case lvm.LUA_OPSHR:
+        case lvm.LUA_OPBNOT: {  /* operate only on integers */
+            let i1 = lvm.tointeger(p1);
+            let i2 = lvm.tointeger(p2);
+            if (i1 !== false && i2 !== false) {
+                res.type  = CT.LUA_TNUMINT;
+                res.value = lobject.intarith(L, op, i1, i2);
+                return;
+            }
+            else break;  /* go to the end */
+        }
+        case lvm.LUA_OPDIV: case lvm.LUA_OPPOW: {  /* operate only on floats */
+            let n1 = lvm.tonumber(p1);
+            let n2 = lvm.tonumber(p2);
+            if (n1 !== false && n2 !== false) {
+                res.type  = CT.LUA_TNUMFLT;
+                res.value = lobject.numarith(L, op, n1, n2);
+                return;
+            }
+            else break;  /* go to the end */
+        }
+        default: {  /* other operations */
+            let n1 = lvm.tonumber(p1);
+            let n2 = lvm.tonumber(p2);
+            if (p1.ttisinteger() && p2.ttisinteger()) {
+                res.type  = CT.LUA_TNUMINT;
+                res.value = lobject.intarith(L, op, p1.value, p2.value);
+                return;
+            }
+            else if (n1 !== false && n2 !== false) {
+                res.type  = CT.LUA_TNUMFLT;
+                res.value = lobject.numarith(L, op, n1, n2);
+                return;
+            }
+            else break;  /* go to the end */
+        }
+    }
+    /* could not perform raw operation; try metamethod */
+    assert(L !== null);  /* should not fail when folding (compile time) */
+    ltm.luaT_trybinTM(L, p1, p2, res, (op - lua.LUA_OPADD) + ltm.TMS.TM_ADD);
+};
+
+/* Maximum number of registers in a Lua function (must fit in 8 bits) */
+const MAXREGS = 255;
+
+/*
+** Marks the end of a patch list. It is an invalid value both as an absolute
+** address, and as a list link (would link an element to itself).
+*/
+const NO_JUMP = -1;
+
+const BinOpr = {
+    OPR_ADD:      0,
+    OPR_SUB:      1,
+    OPR_MUL:      2,
+    OPR_MOD:      3,
+    OPR_POW:      4,
+    OPR_DIV:      5,
+    OPR_IDIV:     6,
+    OPR_BAND:     7,
+    OPR_BOR:      8,
+    OPR_BXOR:     9,
+    OPR_SHL:      10,
+    OPR_SHR:      11,
+    OPR_CONCAT:   12,
+    OPR_EQ:       13,
+    OPR_LT:       14,
+    OPR_LE:       15,
+    OPR_NE:       16,
+    OPR_GT:       17,
+    OPR_GE:       18,
+    OPR_AND:      19,
+    OPR_OR:       21,
+    OPR_NOBINOPR: 22
+};
+
+const UnOpr = {
+    OPR_MINUS:    0,
+    OPR_BNOT:     1,
+    OPR_NOT:      2,
+    OPR_LEN:      3,
+    OPR_NOUNOPR:  4
+};
+
+const hasjumps = function(e) {
+    return e.t !== e.f;
+};
+
+/*
+** If expression is a numeric constant, fills 'v' with its value
+** and returns true. Otherwise, returns false.
+*/
+const tonumeral = function(e, v) {
+    let ek = lparser.expkind;
+    if (hasjumps(e))
+        return false;  /* not a numeral */
+    switch (e.k) {
+        case ek.VKINT:
+            if (v) {
+                v.type = CT.LUA_TNUMINT;
+                v.value = e.u.ival;
+            }
+            return true;
+        case ek.VKFLT:
+            if (v) {
+                v.type = CT.LUA_TNUMFLT;
+                v.value = e.u.nval;
+            }
+            return true;
+        default: return false;
+    }
+};
+
+/*
+** Create a OP_LOADNIL instruction, but try to optimize: if the previous
+** instruction is also OP_LOADNIL and ranges are compatible, adjust
+** range of previous instruction instead of emitting a new one. (For
+** instance, 'local a; local b' will generate a single opcode.)
+*/
+const luaK_nil = function(fs, from, n) {
+    let previous;
+    let l = from + n - 1;  /* last register to set nil */
+    if (fs.pc > fs.lasttarget) {  /* no jumps to current position? */
+        previous = fs.f.code[fs.pc-1];
+        if (previous.opcode === OpCodesI.OP_LOADNIL) {  /* previous is LOADNIL? */
+            let pfrom = previous.A;  /* get previous range */
+            let pl = pfrom + previous.B;
+            if ((pfrom <= from && from <= pl + 1) ||
+                    (from <= pfrom && pfrom <= l + 1)) {  /* can connect both? */
+                if (pfrom < from) from = pfrom;  /* from = min(from, pfrom) */
+                if (pl > l) l = pl;  /* l = max(l, pl) */
+                lopcode.SETARG_A(previous, from);
+                lopcode.SETARG_B(previous, l - from);
+                return;
+            }
+        }  /* else go through */
+    }
+    luaK_codeABC(fs, OpCodesI.OP_LOADNIL, from, n - 1, 0);  /* else no optimization */
+};
+
+const getinstruction = function(fs, e) {
+    return fs.f.code[e.u.info];
+};
+
+/*
+** Gets the destination address of a jump instruction. Used to traverse
+** a list of jumps.
+*/
+const getjump = function(fs, pc) {
+    let offset = fs.f.code[pc].sBx;
+    if (offset === NO_JUMP)  /* point to itself represents end of list */
+        return NO_JUMP;  /* end of list */
+    else
+        return pc + 1 + offset;  /* turn offset into absolute position */
+};
+
+/*
+** Fix jump instruction at position 'pc' to jump to 'dest'.
+** (Jump addresses are relative in Lua)
+*/
+const fixjump = function(fs, pc, dest) {
+    let jmp = fs.f.code[pc];
+    let offset = dest - (pc + 1);
+    assert(dest !== NO_JUMP);
+    if (Math.abs(offset) > lopcode.MAXARG_sBx)
+        llex.luaX_syntaxerror(fs.ls, "control structure too long");
+    lopcode.SETARG_sBx(jmp, offset);
+};
+
+/*
+** Concatenate jump-list 'l2' into jump-list 'l1'
+*/
+const luaK_concat = function(fs, l1, l2) {
+    if (l2 === NO_JUMP) return;  /* nothing to concatenate? */
+    else if (l1 === NO_JUMP)  /* no original list? */
+        l1 = l2;
+    else {
+        let list = l1;
+        let next = getjump(fs, list);
+        while (next !== NO_JUMP) {  /* find last element */
+            list = next;
+            next = getjump(fs, list);
+        }
+        fixjump(fs, list, l2);
+    }
+
+    return l1;
+};
+
+/*
+** Create a jump instruction and return its position, so its destination
+** can be fixed later (with 'fixjump'). If there are jumps to
+** this position (kept in 'jpc'), link them all together so that
+** 'patchlistaux' will fix all them directly to the final destination.
+*/
+const luaK_jump = function (fs) {
+    let jpc = fs.jpc;  /* save list of jumps to here */
+    fs.jpc = NO_JUMP;  /* no more jumps to here */
+    let j = luaK_codeAsBx(fs, OpCodesI.OP_JMP, 0, NO_JUMP);
+    j = luaK_concat(fs, j, jpc);  /* keep them on hold */
+    return j;
+};
+
+const luaK_jumpto = function(fs, t) {
+    return luaK_patchlist(fs, luaK_jump(fs), t);
+};
+
+/*
+** Code a 'return' instruction
+*/
+const luaK_ret = function(fs, first, nret) {
+    luaK_codeABC(fs, OpCodesI.OP_RETURN, first, nret + 1, 0);
+};
+
+/*
+** Code a "conditional jump", that is, a test or comparison opcode
+** followed by a jump. Return jump position.
+*/
+const condjump = function(fs, op, A, B, C) {
+   luaK_codeABC(fs, op, A, B, C);
+   return luaK_jump(fs);
+};
+
+/*
+** returns current 'pc' and marks it as a jump target (to avoid wrong
+** optimizations with consecutive instructions not in the same basic block).
+*/
+const luaK_getlabel = function(fs) {
+    fs.lasttarget = fs.pc;
+    return fs.pc;
+};
+
+/*
+** Returns the position of the instruction "controlling" a given
+** jump (that is, its condition), or the jump itself if it is
+** unconditional.
+*/
+const getjumpcontrol = function(fs, pc) {
+    if (pc >= 1 && lopcode.testTMode(fs.f.code[pc - 1].opcode))
+        return fs.f.code[pc - 1];
+    else
+        return fs.f.code[pc];
+};
+
+/*
+** Patch destination register for a TESTSET instruction.
+** If instruction in position 'node' is not a TESTSET, return 0 ("fails").
+** Otherwise, if 'reg' is not 'NO_REG', set it as the destination
+** register. Otherwise, change instruction to a simple 'TEST' (produces
+** no register value)
+*/
+const patchtestreg = function(fs, node, reg) {
+    let i = getjumpcontrol(fs, node);
+    if (i.opcode !== OpCodesI.OP_TESTSET)
+        return false;  /* cannot patch other instructions */
+    if (reg !== lopcode.NO_REG && reg !== i.B)
+        lopcode.SETARG_A(i, reg);
+    else {
+        /* no register to put value or register already has the value;
+           change instruction to simple test */
+        i = lopcode.CREATE_ABC(OpCodesI.OP_TEST, i.B, 0, i.C);
+    }
+    return true;
+};
+
+/*
+** Traverse a list of tests ensuring no one produces a value
+*/
+const removevalues = function(fs, list) {
+    for (; list !== NO_JUMP; list = getjump(fs, list))
+        patchtestreg(fs, list, lopcode.NO_REG);
+};
+
+/*
+** Traverse a list of tests, patching their destination address and
+** registers: tests producing values jump to 'vtarget' (and put their
+** values in 'reg'), other tests jump to 'dtarget'.
+*/
+const patchlistaux = function(fs, list, vtarget, reg, dtarget) {
+    while (list !== NO_JUMP) {
+        let next = getjump(fs, list);
+        if (patchtestreg(fs, list, reg))
+            fixjump(fs, list, vtarget);
+        else
+            fixjump(fs, list, dtarget);  /* jump to default target */
+        list = next;
+    }
+};
+
+/*
+** Ensure all pending jumps to current position are fixed (jumping
+** to current position with no values) and reset list of pending
+** jumps
+*/
+const dischargejpc = function(fs) {
+    patchlistaux(fs, fs.jpc, fs.pc, lopcode.NO_REG, fs.pc);
+    fs.jpc = NO_JUMP;
+};
+
+/*
+** Add elements in 'list' to list of pending jumps to "here"
+** (current position)
+*/
+const luaK_patchtohere = function(fs, list) {
+    luaK_getlabel(fs);  /* mark "here" as a jump target */
+    fs.jpc = luaK_concat(fs, fs.jpc, list);
+};
+
+/*
+** Path all jumps in 'list' to jump to 'target'.
+** (The assert means that we cannot fix a jump to a forward address
+** because we only know addresses once code is generated.)
+*/
+const luaK_patchlist = function(fs, list, target) {
+    if (target === fs.pc)  /* 'target' is current position? */
+        luaK_patchtohere(fs, list);  /* add list to pending jumps */
+    else {
+        assert(target < fs.pc);
+        patchlistaux(fs, list, target, lopcode.NO_REG, target);
+    }
+};
+
+/*
+** Path all jumps in 'list' to close upvalues up to given 'level'
+** (The assertion checks that jumps either were closing nothing
+** or were closing higher levels, from inner blocks.)
+*/
+const luaK_patchclose = function(fs, list, level) {
+    level++;  /* argument is +1 to reserve 0 as non-op */
+    for (; list !== NO_JUMP; list = getjump(fs, list)) {
+        let ins = fs.f.code[list];
+        assert(ins.opcode === OpCodesI.OP_JMP && (ins.A === 0 || ins.A >= level));
+        lopcode.SETARG_A(ins, level);
+    }
+};
+
+/*
+** Emit instruction 'i', checking for array sizes and saving also its
+** line information. Return 'i' position.
+*/
+const luaK_code = function(fs, i) {
+    let f = fs.f;
+    dischargejpc(fs);  /* 'pc' will change */
+    /* put new instruction in code array */
+    f.code[fs.pc] = i;
+    f.lineinfo[fs.pc] = fs.ls.lastline;
+    return fs.pc++;
+};
+
+/*
+** Format and emit an 'iABC' instruction. (Assertions check consistency
+** of parameters versus opcode.)
+*/
+const luaK_codeABC = function(fs, o, a, b, c) {
+    assert(lopcode.getOpMode(o) === lopcode.iABC);
+    assert(lopcode.getBMode(o) !== lopcode.OpArgN || b === 0);
+    assert(lopcode.getCMode(o) !== lopcode.OpArgN || c === 0);
+    assert(a <= lopcode.MAXARG_A && b <= lopcode.MAXARG_B && c <= lopcode.MAXARG_C);
+    return luaK_code(fs, lopcode.CREATE_ABC(o, a, b, c));
+};
+
+/*
+** Format and emit an 'iABx' instruction.
+*/
+const luaK_codeABx = function(fs, o, a, bc) {
+    assert(lopcode.getOpMode(o) === lopcode.iABx || lopcode.getOpMode(o) === lopcode.iAsBx);
+    assert(lopcode.getCMode(o) === lopcode.OpArgN);
+    assert(a <= lopcode.MAXARG_A && bc <= lopcode.MAXARG_Bx);
+    return luaK_code(fs, lopcode.CREATE_ABx(o, a, bc));
+};
+
+const luaK_codeAsBx = function(fs,o,A,sBx) {
+    return luaK_codeABx(fs, o, A, (sBx) + lopcode.MAXARG_sBx);
+};
+
+/*
+** Emit an "extra argument" instruction (format 'iAx')
+*/
+const codeextraarg = function(fs, a) {
+    assert(a <= lopcode.MAXARG_Ax);
+    return luaK_code(fs, lopcode.CREATE_Ax(OpCodesI.OP_EXTRAARG, a));
+};
+
+/*
+** Emit a "load constant" instruction, using either 'OP_LOADK'
+** (if constant index 'k' fits in 18 bits) or an 'OP_LOADKX'
+** instruction with "extra argument".
+*/
+const luaK_codek = function(fs, reg, k) {
+    if (k <= lopcode.MAXARG_Bx)
+        return luaK_codeABx(fs, OpCodesI.OP_LOADK, reg, k);
+    else {
+        let p = luaK_codeABx(fs, OpCodesI.OP_LOADKX, reg, 0);
+        codeextraarg(fs, k);
+        return p;
+    }
+};
+
+/*
+** Check register-stack level, keeping track of its maximum size
+** in field 'maxstacksize'
+*/
+const luaK_checkstack = function(fs, n) {
+    let newstack = fs.freereg + n;
+    if (newstack > fs.f.maxstacksize) {
+        if (newstack >= MAXREGS)
+            llex.luaX_syntaxerror(fs.ls, "function or expression needs to many registers");
+        fs.f.maxstacksize = newstack;
+    }
+};
+
+/*
+** Reserve 'n' registers in register stack
+*/
+const luaK_reserveregs = function(fs, n) {
+   luaK_checkstack(fs, n);
+   fs.freereg += n;
+};
+
+/*
+** Free register 'reg', if it is neither a constant index nor
+** a local variable.
+*/
+const freereg = function(fs, reg) {
+    if (!lopcode.ISK(reg) && reg >= fs.nactvar) {
+        fs.freereg--;
+        assert(reg === fs.freereg);
+    }
+};
+
+/*
+** Free register used by expression 'e' (if any)
+*/
+const freeexp = function(fs, e) {
+    if (e.k === lparser.expkind.VNONRELOC)
+        freereg(fs, e.u.info);
+};
+
+/*
+** Free registers used by expressions 'e1' and 'e2' (if any) in proper
+** order.
+*/
+const freeexps = function(fs, e1, e2) {
+    let r1 = (e1.k === lparser.expkind.VNONRELOC) ? e1.u.info : -1;
+    let r2 = (e2.k === lparser.expkind.VNONRELOC) ? e2.u.info : -1;
+    if (r1 > r2) {
+        freereg(fs, r1);
+        freereg(fs, r2);
+    }
+    else {
+        freereg(fs, r2);
+        freereg(fs, r1);
+    }
+};
+
+
+/*
+** Add constant 'v' to prototype's list of constants (field 'k').
+** Use scanner's table to cache position of constants in constant list
+** and try to reuse constants. Because some values should not be used
+** as keys (nil cannot be a key, integer keys can collapse with float
+** keys), the caller must provide a useful 'key' for indexing the cache.
+*/
+const addk = function(fs, key, v) {
+    let f = fs.f;
+    let idx = fs.ls.h.__index(fs.ls.h, key);  /* index scanner table */
+    if (idx && !idx.ttisnil()) {  /* is there an index there? */
+        /* correct value? (warning: must distinguish floats from integers!) */
+        if (f.k[idx].ttype() === v.ttype() && f.k[idx].value === v.value)
+            return idx;  /* reuse index */
+    }
+    /* constant not found; create a new entry */
+    let k = fs.nk;
+    fs.ls.h.__newindex(fs.ls.h, key, k);
+    f.k[k] = v;
+    fs.nk++;
+    return k;
+};
+
+/*
+** Add a string to list of constants and return its index.
+*/
+const luaK_stringK = function(fs, s) {
+    return addk(fs, s, s);  /* use string itself as key */
+};
+
+
+/*
+** Add an integer to list of constants and return its index.
+** Integers use userdata as keys to avoid collision with floats with
+** same value; conversion to 'void*' is used only for hashing, so there
+** are no "precision" problems.
+*/
+const luaK_intK = function(fs, n) {
+    let k = new TValue(CT.LUA_TLNGSTR, `${n.value}`);
+    let o = new TValue(CT.LUA_TNUMINT, n.value);
+    return addk(fs, k, o);
+};
+
+/*
+** Add a float to list of constants and return its index.
+*/
+const luaK_numberK = function(fs, r) {
+    return addk(fs, r, r);  /* use number itself as key */
+};
+
+
+/*
+** Add a boolean to list of constants and return its index.
+*/
+const boolK = function(fs, b) {
+    return addk(fs, b, b);  /* use boolean itself as key */
+};
+
+
+/*
+** Add nil to list of constants and return its index.
+*/
+const nilK = function(fs) {
+    return addk(fs, new TValue(CT.LUA_TLNGSTR, `null`), new TValue(CT.LUA_TNIL, null));
+};
+
+/*
+** Fix an expression to return the number of results 'nresults'.
+** Either 'e' is a multi-ret expression (function call or vararg)
+** or 'nresults' is LUA_MULTRET (as any expression can satisfy that).
+*/
+const luaK_setreturns = function(fs, e, nresults) {
+    let ek = lparser.expkind;
+    if (e.k === ek.VCALL) {  /* expression is an open function call? */
+        lopcode.SETARG_C(getinstruction(fs, e), nresults + 1);
+    }
+    else if (e.k === ek.VVARARG) {
+        let pc = getinstruction(fs, e);
+        lopcode.SETARG_B(pc, nresults + 1);
+        lopcode.SETARG_A(pc, fs.freereg);
+        luaK_reserveregs(fs, 1);
+    }
+    else assert(nresults === lua.LUA_MULTRET);
+};
+
+const luaK_setmultret = function(fs, e) {
+    luaK_setreturns(fs, e, lua.LUA_MULTRET);
+};
+
+/*
+** Fix an expression to return one result.
+** If expression is not a multi-ret expression (function call or
+** vararg), it already returns one result, so nothing needs to be done.
+** Function calls become VNONRELOC expressions (as its result comes
+** fixed in the base register of the call), while vararg expressions
+** become VRELOCABLE (as OP_VARARG puts its results where it wants).
+** (Calls are created returning one result, so that does not need
+** to be fixed.)
+*/
+const luaK_setoneret = function(fs, e) {
+    let ek = lparser.expkind;
+    if (e.k === ek.VCALL) {  /* expression is an open function call? */
+        /* already returns 1 value */
+        assert(getinstruction(fs, e).C === 2);
+        e.k = ek.VNONRELOC;  /* result has fixed position */
+        e.u.info = getinstruction(fs, e).A;
+    } else if (e.k === ek.VVARARG) {
+        lopcode.SETARG_B(getinstruction(fs, e), 2);
+        e.k = ek.VRELOCABLE;  /* can relocate its simple result */
+    }
+};
+
+/*
+** Ensure that expression 'e' is not a variable.
+*/
+const luaK_dischargevars = function(fs, e) {
+    let ek = lparser.expkind;
+
+    switch (e.k) {
+        case ek.VLOCAL: {  /* already in a register */
+            e.k =  ek.VNONRELOC;  /* becomes a non-relocatable value */
+            break;
+        }
+        case ek.VUPVAL: {  /* move value to some (pending) register */
+            e.u.info = luaK_codeABC(fs, OpCodesI.OP_GETUPVAL, 0, e.u.info, 0);
+            e.k = ek.VRELOCABLE;
+            break;
+        }
+        case ek.VINDEXED: {
+            let op;
+            freereg(fs, e.u.ind.idx);
+            if (e.u.ind.vt === ek.VLOCAL) {  /* is 't' in a register? */
+                freereg(fs, e.u.ind.t);
+                op = OpCodesI.OP_GETTABLE;
+            } else {
+                assert(e.u.ind.vt === ek.VUPVAL);
+                op = OpCodesI.OP_GETTABUP;  /* 't' is in an upvalue */
+            }
+            e.u.info = luaK_codeABC(fs, op, 0, e.u.ind.t, e.u.ind.idx);
+            e.k = OpCodesI.VRELOCABLE;
+            break;
+        }
+        case ek.VVARARG: case ek.VCALL: {
+            luaK_setoneret(fs, e);
+            break;
+        }
+        default: break;  /* there is one value available (somewhere) */
+    }
+};
+
+const code_loadbool = function(fs, A, b, jump) {
+    luaK_getlabel(fs);  /* those instructions may be jump targets */
+    return luaK_codeABC(fs, OpCodesI.OP_LOADBOOL, A, b, jump);
+};
+
+/*
+** Ensures expression value is in register 'reg' (and therefore
+** 'e' will become a non-relocatable expression).
+*/
+const discharge2reg = function(fs, e, reg) {
+    let ek = lparser.expkind;
+    luaK_dischargevars(fs, e);
+    switch (e.k) {
+        case ek.VNIL: {
+            luaK_nil(fs, reg, 1);
+            break;
+        }
+        case ek.VFALSE: case ek.VTRUE: {
+            luaK_codeABC(fs, OpCodesI.OP_LOADBOOL, reg, e.k === ek.VTRUE, 0);
+            break;
+        }
+        case ek.VK: {
+            luaK_codek(fs, reg, e.u.info);
+            break;
+        }
+        case ek.VKFLT: {
+            luaK_codek(fs, reg, luaK_numberK(fs, e.u.nval));
+            break;
+        }
+        case ek.VKINT: {
+            luaK_codek(fs, reg, luaK_intK(fs, e.u.ival));
+            break;
+        }
+        case ek.VRELOCABLE: {
+            let pc = getinstruction(fs, e);
+            lopcode.SETARG_A(pc, reg);  /* instruction will put result in 'reg' */
+            break;
+        }
+        case ek.VNONRELOC: {
+            if (reg !== e.u.info)
+                luaK_codeABC(fs, OpCodesI.OP_MOVE, reg, e.u.info, 0);
+            break;
+        }
+        default: {
+            assert(e.k === ek.VJMP);
+            return;  /* nothing to do... */
+        }
+    }
+    e.u.info = reg;
+    e.k = ek.VNONRELOC;
+};
+
+/*
+** Ensures expression value is in any register.
+*/
+const discharge2anyreg = function(fs, e) {
+    if (e.k !== lparser.expkind.VNONRELOC) {  /* no fixed register yet? */
+        luaK_reserveregs(fs, 1);  /* get a register */
+        discharge2reg(fs, e, fs.freereg-1);  /* put value there */
+    }
+};
+
+/*
+** check whether list has any jump that do not produce a value
+** or produce an inverted value
+*/
+const need_value = function(fs, list) {
+    for (; list !== NO_JUMP; list = getjump(fs, list)) {
+        let i = getjumpcontrol(fs, list);
+        if (i.opcode !== OpCodesI.OP_TESTSET) return true;
+    }
+    return false;  /* not found */
+};
+
+/*
+** Ensures final expression result (including results from its jump
+** lists) is in register 'reg'.
+** If expression has jumps, need to patch these jumps either to
+** its final position or to "load" instructions (for those tests
+** that do not produce values).
+*/
+const exp2reg = function(fs, e, reg) {
+    let ek = lparser.expkind;
+    discharge2reg(fs, e, reg);
+    if (e.k === ek.VJMP)  /* expression itself is a test? */
+        e.t = luaK_concat(fs, e.t, e.u.info);  /* put this jump in 't' list */
+    if (hasjumps(e)) {
+        let final;  /* position after whole expression */
+        let p_f = NO_JUMP;  /* position of an eventual LOAD false */
+        let p_t = NO_JUMP;  /* position of an eventual LOAD true */
+        if (need_value(fs, e.t) || need_value(fs, e.f)) {
+            let fj = (e.k === ek.VJMP) ? NO_JUMP : luaK_jump(fs);
+            p_f = code_loadbool(fs, reg, 0, 1);
+            p_t = code_loadbool(fs, reg, 1, 0);
+            luaK_patchtohere(fs, fj);
+        }
+        final = luaK_getlabel(fs);
+        patchlistaux(fs, e.f, final, reg, p_f);
+        patchlistaux(fs, e.t, final, reg, p_t);
+    }
+    e.f = e.t = NO_JUMP;
+    e.u.info = reg;
+    e.k = ek.VNONRELOC;
+};
+
+/*
+** Ensures final expression result (including results from its jump
+** lists) is in next available register.
+*/
+const luaK_exp2nextreg = function(fs, e) {
+    luaK_dischargevars(fs, e);
+    freeexp(fs, e);
+    luaK_reserveregs(fs, 1);
+    exp2reg(fs, e, fs.freereg - 1);
+};
+
+
+/*
+** Ensures final expression result (including results from its jump
+** lists) is in some (any) register and return that register.
+*/
+const luaK_exp2anyreg = function(fs, e) {
+    luaK_dischargevars(fs, e);
+    if (e.k === lparser.expkind.VNONRELOC) {  /* expression already has a register? */
+        if (!hasjumps(e))  /* no jumps? */
+            return e.u.info;  /* result is already in a register */
+        if (e.u.info >= fs.nactvar) {  /* reg. is not a local? */
+            exp2reg(fs, e, e.u.info);  /* put final result in it */
+            return e.u.info;
+        }
+    }
+    luaK_exp2nextreg(fs, e);  /* otherwise, use next available register */
+    return e.u.info;
+};
+
+/*
+** Ensures final expression result is either in a register or in an
+** upvalue.
+*/
+const luaK_exp2anyregup = function(fs, e) {
+    if (e.k !== lparser.expkind.VUPVAL || hasjumps(e))
+        luaK_exp2anyreg(fs, e);
+};
+
+/*
+** Ensures final expression result is either in a register or it is
+** a constant.
+*/
+const luaK_exp2val = function(fs, e) {
+    if (hasjumps(e))
+        luaK_exp2anyreg(fs, e);
+    else
+        luaK_dischargevars(fs, e);
+};
+
+/*
+** Ensures final expression result is in a valid R/K index
+** (that is, it is either in a register or in 'k' with an index
+** in the range of R/K indices).
+** Returns R/K index.
+*/
+const luaK_exp2RK = function(fs, e) {
+    let ek = lparser.expkind;
+    let vk = false;
+    luaK_exp2val(fs, e);
+    switch (e.k) {  /* move constants to 'k' */
+        case ek.VTRUE: e.u.info = boolK(fs, 1); vk = true; break;
+        case ek.VFALSE: e.u.info = boolK(fs, 0); vk = true; break;
+        case ek.VNIL: e.u.info = nilK(fs); vk = true; break;
+        case ek.VKINT: e.u.info = luaK_intK(fs, e.u.ival); vk = true; break;
+        case ek.VKFLT: e.u.info = luaK_numberK(fs, e.u.nval); vk = true; break;
+        case ek.VK: vk = true; break;
+        default: break;
+    }
+
+    if (vk) {
+        e.k = ek.VK;
+        if (e.u.info <= lopcode.MAXINDEXRK)  /* constant fits in 'argC'? */
+            return lopcode.RKASK(e.u.info);
+    }
+
+    /* not a constant in the right range: put it in a register */
+    return luaK_exp2anyreg(fs, e);
+};
+
+/*
+** Generate code to store result of expression 'ex' into variable 'var'.
+*/
+const luaK_storevar = function(fs, vr, ex) {
+    let ek = lparser.expkind;
+    switch (vr.k) {
+        case ek.VLOCAL: {
+            freeexp(fs, ex);
+            exp2reg(fs, ex, vr.u.info);  /* compute 'ex' into proper place */
+            return;
+        }
+        case ek.VUPVAL: {
+            let e = luaK_exp2anyreg(fs, ex);
+            luaK_codeABC(fs, OpCodesI.OP_SETUPVAL, e, vr.u.info, 0);
+          break;
+        }
+        case ek.VINDEXED: {
+            let op = (vr.u.ind.vt === ek.VLOCAL) ? OpCodesI.OP_SETTABLE : OpCodesI.OP_SETTABUP;
+            let e = luaK_exp2RK(fs, ex);
+            luaK_codeABC(fs, op, vr.u.ind.t, vr.u.ind.idx, e);
+            break;
+        }
+    }
+    freeexp(fs, ex);
+};
+
+
+/*
+** Emit SELF instruction (convert expression 'e' into 'e:key(e,').
+*/
+const luaK_self = function(fs, e, key) {
+    luaK_exp2anyreg(fs, e);
+    let ereg = e.u.info;  /* register where 'e' was placed */
+    freeexp(fs, e);
+    e.u.info = fs.freereg;  /* base register for op_self */
+    e.k = lparser.expkind.VNONRELOC;  /* self expression has a fixed register */
+    luaK_reserveregs(fs, 2);  /* function and 'self' produced by op_self */
+    luaK_codeABC(fs, OpCodesI.OP_SELF, e.u.info, ereg, luaK_exp2RK(fs, key));
+    freeexp(fs, key);
+};
+
+/*
+** Negate condition 'e' (where 'e' is a comparison).
+*/
+const negatecondition = function(fs, e) {
+    let pc = getjumpcontrol(fs, e.u.info);
+    assert(lopcode.testTMode(pc.opcode) && pc.opcode !== OpCodesI.OP_TESTSET && pc.opcode !== OpCodesI.OP_TEST);
+    lopcode.SETARG_A(pc, !(pc.A));
+};
+
+/*
+** Emit instruction to jump if 'e' is 'cond' (that is, if 'cond'
+** is true, code will jump if 'e' is true.) Return jump position.
+** Optimize when 'e' is 'not' something, inverting the condition
+** and removing the 'not'.
+*/
+const jumponcond = function(fs, e, cond) {
+    if (e.k === lparser.expkind.VRELOCABLE) {
+        let ie = getinstruction(fs, e);
+        if (ie.opcode === OpCodesI.OP_NOT) {
+            fs.pc--;  /* remove previous OP_NOT */
+            return condjump(fs, OpCodesI.OP_TEST, ie.B, 0, !cond);
+        }
+        /* else go through */
+    }
+    discharge2anyreg(fs, e);
+    freeexp(fs, e);
+    return condjump(fs, OpCodesI.OP_TESTSET, lopcode.NO_REG, e.u.info, cond);
+};
+
+/*
+** Emit code to go through if 'e' is true, jump otherwise.
+*/
+const luaK_goiftrue = function(fs, e) {
+    let ek = lparser.expkind;
+    let pc;  /* pc of new jump */
+    luaK_dischargevars(fs, e);
+    switch (e.k) {
+        case ek.VJMP: {  /* condition? */
+           negatecondition(fs, e);  /* jump when it is false */
+           pc = e.u.info;  /* save jump position */
+           break;
+        }
+        case ek.VK: case ek.VKFLT: case ek.VKINT: case ek.VTRUE: {
+           pc = NO_JUMP;  /* always true; do nothing */
+           break;
+        }
+        default: {
+           pc = jumponcond(fs, e, 0);  /* jump when false */
+           break;
+        }
+    }
+    e.f = luaK_concat(fs, e.f, pc);  /* insert new jump in false list */
+    luaK_patchtohere(fs, e.t);  /* true list jumps to here (to go through) */
+    e.t = NO_JUMP;
+};
+
+/*
+** Emit code to go through if 'e' is false, jump otherwise.
+*/
+const luaK_goiffalse = function(fs, e) {
+    let ek = lparser.expkind;
+    let pc;  /* pc of new jump */
+    luaK_dischargevars(fs, e);
+    switch (e.k) {
+        case ek.VJMP: {
+            pc = e.u.info;  /* already jump if true */
+            break;
+        }
+        case ek.VNIL: case ek.VFALSE: {
+            pc = NO_JUMP;  /* always false; do nothing */
+            break;
+        }
+        default: {
+            pc = jumponcond(fs, e, 1);  /* jump if true */
+            break;
+        }
+    }
+    e.t = luaK_concat(fs, e.t, pc);  /* insert new jump in 't' list */
+    luaK_patchtohere(fs, e.f);  /* false list jumps to here (to go through) */
+    e.f = NO_JUMP;
+};
+
+/*
+** Code 'not e', doing constant folding.
+*/
+const codenot = function(fs, e) {
+    let ek = lparser.expkind;
+    luaK_dischargevars(fs, e);
+    switch (e.k) {
+        case ek.VNIL: case ek.VFALSE: {
+            e.k = ek.VTRUE;  /* true === not nil === not false */
+            break;
+        }
+        case ek.VK: case ek.VKFLT: case ek.VKINT: case ek.VTRUE: {
+            e.k = ek.VFALSE;  /* false === not "x" === not 0.5 === not 1 === not true */
+            break;
+        }
+        case ek.VJMP: {
+            negatecondition(fs, e);
+            break;
+        }
+        case ek.VRELOCABLE:
+        case ek.VNONRELOC: {
+            discharge2anyreg(fs, e);
+            freeexp(fs, e);
+            e.u.info = luaK_codeABC(fs, OpCodesI.OP_NOT, 0, e.u.info, 0);
+            e.k = ek.VRELOCABLE;
+            break;
+        }
+    }
+    /* interchange true and false lists */
+    { let temp = e.f; e.f = e.t; e.t = temp; }
+    removevalues(fs, e.f);  /* values are useless when negated */
+    removevalues(fs, e.t);
+};
+
+/*
+** Create expression 't[k]'. 't' must have its final result already in a
+** register or upvalue.
+*/
+const luaK_indexed = function(fs, t, k) {
+    let ek = lparser.expkind;
+    assert(!hasjumps(t) && (lparser.vkisinreg(t.k) || t.k === ek.VUPVAL));
+    t.u.ind.t = t.u.info;  /* register or upvalue index */
+    t.u.ind.idx = luaK_exp2RK(fs, k);  /* R/K index for key */
+    t.u.ind.vt = (t.k === ek.VUPVAL) ? ek.VUPVAL : ek.VLOCAL;
+    t.k = ek.VINDEXED;
+};
+
+/*
+** Return false if folding can raise an error.
+** Bitwise operations need operands convertible to integers; division
+** operations cannot have 0 as divisor.
+*/
+const validop = function(op, v1, v2) {
+    switch (op) {
+        case lua.LUA_OPBAND: case lua.LUA_OPBOR: case lua.LUA_OPBXOR:
+        case lua.LUA_OPSHL: case lua.LUA_OPSHR: case lua.LUA_OPBNOT: {  /* conversion errors */
+            return (lvm.tointeger(v1) && lvm.tointeger(v2));
+        }
+        case lua.LUA_OPDIV: case lua.LUA_OPIDIV: case lua.LUA_OPMOD:  /* division by 0 */
+            return (v2.value !== 0);
+        default: return 1;  /* everything else is valid */
+    }
+};
+
+/*
+** Try to "constant-fold" an operation; return 1 iff successful.
+** (In this case, 'e1' has the final result.)
+*/
+const constfolding = function(fs, op, e1, e2) {
+    let ek = lparser.expkind;
+    let v1 = new TValue();
+    let v2 = new TValue();
+    let res = new TValue();
+    if (!tonumeral(e1, v1) || !tonumeral(e2, v2) || !validop(op, v1, v2))
+        return 0;  /* non-numeric operands or not safe to fold */
+    luaO_arith(fs.ls.L, op, v1, v2, res);  /* does operation */
+    if (res.ttisinteger()) {
+        e1.k = ek.VKINT;
+        e1.u.ival = res.value;
+    }
+    else {  /* folds neither NaN nor 0.0 (to avoid problems with -0.0) */
+        let n = res.value;
+        if (isNaN(n) || n === 0)
+            return false;
+        e1.k = ek.VKFLT;
+        e1.u.nval = n;
+    }
+    return true;
+};
+
+/*
+** Emit code for unary expressions that "produce values"
+** (everything but 'not').
+** Expression to produce final result will be encoded in 'e'.
+*/
+const codeunexpval = function(fs, op, e, line) {
+   let r = luaK_exp2anyreg(fs, e);  /* opcodes operate only on registers */
+   freeexp(fs, e);
+   e.u.info = luaK_codeABC(fs, op, 0, r, 0);  /* generate opcode */
+   e.k = lparser.expkind.VRELOCABLE;  /* all those operations are relocatable */
+   luaK_fixline(fs, line);
+};
+
+/*
+** Emit code for binary expressions that "produce values"
+** (everything but logical operators 'and'/'or' and comparison
+** operators).
+** Expression to produce final result will be encoded in 'e1'.
+** Because 'luaK_exp2RK' can free registers, its calls must be
+** in "stack order" (that is, first on 'e2', which may have more
+** recent registers to be released).
+*/
+const codebinexpval = function(fs, op, e1, e2, line) {
+    let rk2 = luaK_exp2RK(fs, e2);  /* both operands are "RK" */
+    let rk1 = luaK_exp2RK(fs, e1);
+    freeexps(fs, e1, e2);
+    e1.u.info = luaK_codeABC(fs, op, 0, rk1, rk2);  /* generate opcode */
+    e1.k = lparser.expkind.VRELOCABLE;  /* all those operations are relocatable */
+    luaK_fixline(fs, line);
+};
+
+
+/*
+** Emit code for comparisons.
+** 'e1' was already put in R/K form by 'luaK_infix'.
+*/
+const codecomp = function(fs, opr, e1, e2) {
+    let ek = lparser.expkind;
+    let rk1 = (e1.k === ek.VK) ? lopcode.RKASK(e1.u.info) : llimit.check_exp(e1.k === ek.VNONRELOC, e1.u.info);
+    let rk2 = luaK_exp2RK(fs, e2);
+    freeexps(fs, e1, e2);
+    switch (opr) {
+        case BinOpr.OPR_NE: {  /* '(a ~= b)' ==> 'not (a === b)' */
+            e1.u.info = condjump(fs, OpCodesI.OP_EQ, 0, rk1, rk2);
+            break;
+        }
+        case BinOpr.OPR_GT: case BinOpr.OPR_GE: {
+            /* '(a > b)' ==> '(b < a)';  '(a >= b)' ==> '(b <= a)' */
+            let op = (opr - BinOpr.OPR_NE) + OpCodesI.OP_EQ;
+            e1.u.info = condjump(fs, op, 1, rk2, rk1);  /* invert operands */
+            break;
+        }
+        default: {  /* '==', '<', '<=' use their own opcodes */
+            let op = (opr - BinOpr.OPR_EQ) + OpCodesI.OP_EQ;
+            e1.u.info = condjump(fs, op, 1, rk1, rk2);
+            break;
+        }
+    }
+    e1.k = ek.VJMP;
+};
+
+/*
+** Apply prefix operation 'op' to expression 'e'.
+*/
+const luaK_prefix = function(fs, op, e, line) {
+    let ef = new lparser.expdesc();
+    ef.k = lparser.expkind.VKINT;
+    ef.u.ival = e.u.nval = e.u.info = 0;
+    e.t = NO_JUMP;
+    e.f = NO_JUMP;
+    switch (op) {
+        case UnOpr.OPR_MINUS: case UnOpr.OPR_BNOT:  /* use 'ef' as fake 2nd operand */
+            if (constfolding(fs, op + lua.LUA_OPUNM, e, ef))
+                break;
+            /* FALLTHROUGH */
+        case UnOpr.OPR_LEN:
+            codeunexpval(fs, op + UnOpr.OP_UNM, e, line);
+            break;
+        case UnOpr.OPR_NOT: codenot(fs, e); break;
+    }
+};
+
+/*
+** Process 1st operand 'v' of binary operation 'op' before reading
+** 2nd operand.
+*/
+const luaK_infix = function(fs, op, v) {
+    switch (op) {
+        case BinOpr.OPR_AND: {
+            luaK_goiftrue(fs, v);  /* go ahead only if 'v' is true */
+            break;
+        }
+        case BinOpr.OPR_OR: {
+            luaK_goiffalse(fs, v);  /* go ahead only if 'v' is false */
+            break;
+        }
+        case BinOpr.OPR_CONCAT: {
+            luaK_exp2nextreg(fs, v);  /* operand must be on the 'stack' */
+            break;
+        }
+        case BinOpr.OPR_ADD: case BinOpr.OPR_SUB:
+        case BinOpr.OPR_MUL: case BinOpr.OPR_DIV: case BinOpr.OPR_IDIV:
+        case BinOpr.OPR_MOD: case BinOpr.OPR_POW:
+        case BinOpr.OPR_BAND: case BinOpr.OPR_BOR: case BinOpr.OPR_BXOR:
+        case BinOpr.OPR_SHL: case BinOpr.OPR_SHR: {
+            if (!tonumeral(v, null))
+                luaK_exp2RK(fs, v);
+            /* else keep numeral, which may be folded with 2nd operand */
+            break;
+        }
+        default: {
+            luaK_exp2RK(fs, v);
+            break;
+        }
+    }
+};
+
+/*
+** Finalize code for binary operation, after reading 2nd operand.
+** For '(a .. b .. c)' (which is '(a .. (b .. c))', because
+** concatenation is right associative), merge second CONCAT into first
+** one.
+*/
+const luaK_posfix = function(fs, op, e1, e2, line) {
+    let ek = lparser.expkind;
+    switch (op) {
+        case BinOpr.OPR_AND: {
+            assert(e1.t === NO_JUMP);  /* list closed by 'luK_infix' */
+            luaK_dischargevars(fs, e2);
+            e2.f = luaK_concat(fs, e2.f, e1.f);
+            // WARN: *e1 = *e2;
+            break;
+        }
+        case BinOpr.OPR_OR: {
+            assert(e1.f === NO_JUMP);  /* list closed by 'luK_infix' */
+            luaK_dischargevars(fs, e2);
+            e2.t = luaK_concat(fs, e2.t, e1.t);
+            // WARN: *e1 = *e2;
+            break;
+        }
+        case BinOpr.OPR_CONCAT: {
+            let ins = getinstruction(fs, e2);
+            luaK_exp2val(fs, e2);
+            if (e2.k === ek.VRELOCABLE && ins.opcode === OpCodesI.OP_CONCAT) {
+                assert(e1.u.info === ins.B - 1);
+                freeexp(fs, e1);
+                lopcode.SETARG_B(ins, e1.u.info);
+                e1.k = ek.VRELOCABLE; e1.u.info = e2.u.info;
+            }
+            else {
+                luaK_exp2nextreg(fs, e2);  /* operand must be on the 'stack' */
+                codebinexpval(fs, OpCodesI.OP_CONCAT, e1, e2, line);
+            }
+            break;
+        }
+        case BinOpr.OPR_ADD: case BinOpr.OPR_SUB: case BinOpr.OPR_MUL: case BinOpr.OPR_DIV:
+        case BinOpr.OPR_IDIV: case BinOpr.OPR_MOD: case BinOpr.OPR_POW:
+        case BinOpr.OPR_BAND: case BinOpr.OPR_BOR: case BinOpr.OPR_BXOR:
+        case BinOpr.OPR_SHL: case BinOpr.OPR_SHR: {
+            if (!constfolding(fs, op + lua.LUA_OPADD, e1, e2))
+                codebinexpval(fs, op + OpCodesI.OP_ADD, e1, e2, line);
+            break;
+        }
+        case BinOpr.OPR_EQ: case BinOpr.OPR_LT: case BinOpr.OPR_LE:
+        case BinOpr.OPR_NE: case BinOpr.OPR_GT: case BinOpr.OPR_GE: {
+            codecomp(fs, op, e1, e2);
+            break;
+        }
+    }
+};
+
+/*
+** Change line information associated with current position.
+*/
+const luaK_fixline = function(fs, line) {
+    fs.f.lineinfo[fs.pc - 1] = line;
+};
+
+/*
+** Emit a SETLIST instruction.
+** 'base' is register that keeps table;
+** 'nelems' is #table plus those to be stored now;
+** 'tostore' is number of values (in registers 'base + 1',...) to add to
+** table (or LUA_MULTRET to add up to stack top).
+*/
+const luaK_setlist = function(fs, base, nelems, tostore) {
+    let c =  (nelems - 1)/lopcode.LFIELDS_PER_FLUSH + 1;
+    let b = (tostore === lua.LUA_MULTRET) ? 0 : tostore;
+    assert(tostore !== 0 && tostore <= lopcode.LFIELDS_PER_FLUSH);
+    if (c <= lopcode.MAXARG_C)
+        luaK_codeABC(fs, OpCodesI.OP_SETLIST, base, b, c);
+    else if (c <= lopcode.MAXARG_Ax) {
+        luaK_codeABC(fs, OpCodesI.OP_SETLIST, base, b, 0);
+        codeextraarg(fs, c);
+    }
+    else
+        llex.luaX_syntaxerror(fs.ls, "constructor too long");
+    fs.freereg = base + 1;  /* free registers with list values */
+};
+
+
+module.exports.BinOpr             = BinOpr;
+module.exports.NO_JUMP            = NO_JUMP;
+module.exports.UnOpr              = UnOpr;
+module.exports.getinstruction     = getinstruction;
+module.exports.luaK_checkstack    = luaK_checkstack;
+module.exports.luaK_code          = luaK_code;
+module.exports.luaK_codeABC       = luaK_codeABC;
+module.exports.luaK_codeABx       = luaK_codeABx;
+module.exports.luaK_codeAsBx      = luaK_codeAsBx;
+module.exports.luaK_codek         = luaK_codek;
+module.exports.luaK_concat        = luaK_concat;
+module.exports.luaK_dischargevars = luaK_dischargevars;
+module.exports.luaK_exp2RK        = luaK_exp2RK;
+module.exports.luaK_exp2anyreg    = luaK_exp2anyreg;
+module.exports.luaK_exp2anyregup  = luaK_exp2anyregup;
+module.exports.luaK_exp2nextreg   = luaK_exp2nextreg;
+module.exports.luaK_exp2val       = luaK_exp2val;
+module.exports.luaK_fixline       = luaK_fixline;
+module.exports.luaK_getlabel      = luaK_getlabel;
+module.exports.luaK_goiffalse     = luaK_goiffalse;
+module.exports.luaK_goiftrue      = luaK_goiftrue;
+module.exports.luaK_indexed       = luaK_indexed;
+module.exports.luaK_infix         = luaK_infix;
+module.exports.luaK_intK          = luaK_intK;
+module.exports.luaK_jump          = luaK_jump;
+module.exports.luaK_jumpto        = luaK_jumpto;
+module.exports.luaK_nil           = luaK_nil;
+module.exports.luaK_numberK       = luaK_numberK;
+module.exports.luaK_patchclose    = luaK_patchclose;
+module.exports.luaK_patchlist     = luaK_patchlist;
+module.exports.luaK_patchtohere   = luaK_patchtohere;
+module.exports.luaK_posfix        = luaK_posfix;
+module.exports.luaK_prefix        = luaK_prefix;
+module.exports.luaK_reserveregs   = luaK_reserveregs;
+module.exports.luaK_ret           = luaK_ret;
+module.exports.luaK_self          = luaK_self;
+module.exports.luaK_setlist       = luaK_setlist;
+module.exports.luaK_setmultret    = luaK_setmultret;
+module.exports.luaK_setoneret     = luaK_setoneret;
+module.exports.luaK_setreturns    = luaK_setreturns;
+module.exports.luaK_storevar      = luaK_storevar;
+module.exports.luaK_stringK       = luaK_stringK;
\ No newline at end of file
diff --git a/src/lcorolib.js b/src/lcorolib.js
index 05f3b00..b2d0de8 100644
--- a/src/lcorolib.js
+++ b/src/lcorolib.js
@@ -1,4 +1,3 @@
-/* jshint esversion: 6 */
 "use strict";
 
 const assert  = require('assert');
diff --git a/src/ldebug.js b/src/ldebug.js
index f6d0633..091b896 100644
--- a/src/ldebug.js
+++ b/src/ldebug.js
@@ -60,7 +60,7 @@ const upvalname = function(p, uv) {
 };
 
 const funcinfo = function(ar, cl) {
-    if (cl === null || cl.type == CT.LUA_TCCL) {
+    if (cl === null || cl.type === CT.LUA_TCCL) {
         ar.source = "=[JS]";
         ar.linedefined = -1;
         ar.lastlinedefined = -1;
@@ -77,7 +77,7 @@ const funcinfo = function(ar, cl) {
 };
 
 const collectvalidlines = function(L, f) {
-    if (f === null || f.c.type == CT.LUA_TCCL) {
+    if (f === null || f.c.type === CT.LUA_TCCL) {
         L.stack[L.top++] = ldo.nil;
         assert(L.top <= L.ci.top, "stack overflow");
     } else {
@@ -123,7 +123,7 @@ const auxgetinfo = function(L, what, ar, f, ci) {
             }
             case 'u': {
                 ar.nups = f === null ? 0 : f.c.nupvalues;
-                if (f === null || f.c.type == CT.LUA_TCCL) {
+                if (f === null || f.c.type === CT.LUA_TCCL) {
                     ar.isvararg = true;
                     ar.nparams = 0;
                 } else {
diff --git a/src/ldo.js b/src/ldo.js
index 8d12c9f..efb971d 100644
--- a/src/ldo.js
+++ b/src/ldo.js
@@ -3,15 +3,18 @@
 
 const assert         = require('assert');
 
-const lua            = require('./lua.js');
+const BytecodeParser = require('./lundump.js');
+const lapi           = require('./lapi.js');
+const ldebug         = require('./ldebug.js');
+const lfunc          = require('./lfunc.js');
+const llex           = require('./llex.js');
+const llimit         = require('./llimit.js');
 const lobject        = require('./lobject.js');
+const lparser        = require('./lparser.js');
 const lstate         = require('./lstate.js');
-const llimit         = require('./llimit.js');
 const ltm            = require('./ltm.js');
+const lua            = require('./lua.js');
 const lvm            = require('./lvm.js');
-const lfunc          = require('./lfunc.js');
-const BytecodeParser = require('./lundump.js');
-const ldebug         = require('./ldebug.js');
 const CT             = lua.constant_types;
 const TS             = lua.thread_status;
 const LUA_MULTRET    = lua.LUA_MULTRET;
@@ -475,7 +478,7 @@ const lua_yield = function(L, n) {
 
 const luaD_pcall = function(L, func, u, old_top, ef) {
     let old_ci = L.ci;
-    // TODO: lu_byte old_allowhooks = L->allowhook;
+    let old_allowhooks = L.allowhook;
     let old_nny = L.nny;
     let old_errfunc = L.errfunc;
     L.errfunc = ef;
@@ -486,7 +489,7 @@ const luaD_pcall = function(L, func, u, old_top, ef) {
         lfunc.luaF_close(L, old_top);
         seterrorobj(L, status, old_top);
         L.ci = old_ci;
-        // TODO: L->allowhook = old_allowhooks;
+        L.allowhook = old_allowhooks;
         L.nny = old_nny;
     }
 
@@ -504,31 +507,64 @@ const luaD_callnoyield = function(L, off, nResults) {
   L.nny--;
 };
 
-// TODO: since we only handle binary, no need for a reader or mode
-const f_parser = function(L, data) {
-    let p = new BytecodeParser(data);
-    let cl = p.luaU_undump(L);
+/*
+** Execute a protected parser.
+*/
+class SParser {
+    constructor() {  /* data to 'f_parser' */
+        this.z = new llex.MBuffer();
+        this.buff = new llex.MBuffer();  /* dynamic structure used by the scanner */
+        this.dyd = new lparser.Dyndata();  /* dynamic structures used by the parser */
+        this.mode = null;
+        this.name = null;
+    }
+}
+
+const checkmode = function(L, mode, x) {
+    if (mode && mode !== x) {
+        lapi.lua_pushstring(L, `attempt to load a ${x} chunk (mode is '${mode}')`);
+        luaD_throw(L, TS.LUA_ERRSYNTAX);
+    }
+};
 
-    assert(cl.nupvalues == cl.p.upvalues.length);
+const f_parser = function(L, p) {
+    let cl;
+    let c = p.z.getc();  /* read first character */
+    if (String.fromCharCode(c) === lua.LUA_SIGNATURE.charAt(0)) {
+        checkmode(L, p.mode, "binary");
+        cl = new BytecodeParser(p.z.buffer).luaU_undump(L);
+    } else {
+        checkmode(L, p.mode, "text");
+        cl = lparser.luaY_parser(L, p.z, p.buff, p.dyd, p.name, c);
+    }
 
+    assert(cl.nupvalues === cl.p.upvalues.length);
     lfunc.luaF_initupvals(L, cl);
 };
 
-const luaD_protectedparser = function(L, data, name) {
-    L.nny++;
+const luaD_protectedparser = function(L, z, name, mode) {
+    let p = new SParser();
+    L.nny++;  /* cannot yield during parsing */
 
-    let status = luaD_pcall(L, f_parser, data, L.top, L.errfunc);
+    p.z = z;
+    p.name = name;
+    p.mode = mode;
+    p.dyd.actvar.arr = [];
+    p.dyd.actvar.size = 0;
+    p.dyd.gt.arr = [];
+    p.dyd.gt.size = 0;
+    p.dyd.label.arr = [];
+    p.dyd.label.size = 0;
+
+    let status = luaD_pcall(L, f_parser, p, L.top, L.errfunc);
 
     L.nny--;
 
     return status;
 };
 
+module.exports.SParser              = SParser;
 module.exports.adjust_varargs       = adjust_varargs;
-module.exports.lua_isyieldable      = lua_isyieldable;
-module.exports.lua_resume           = lua_resume;
-module.exports.lua_yield            = lua_yield;
-module.exports.lua_yieldk           = lua_yieldk;
 module.exports.luaD_call            = luaD_call;
 module.exports.luaD_callnoyield     = luaD_callnoyield;
 module.exports.luaD_pcall           = luaD_pcall;
@@ -537,6 +573,10 @@ module.exports.luaD_precall         = luaD_precall;
 module.exports.luaD_protectedparser = luaD_protectedparser;
 module.exports.luaD_rawrunprotected = luaD_rawrunprotected;
 module.exports.luaD_throw           = luaD_throw;
+module.exports.lua_isyieldable      = lua_isyieldable;
+module.exports.lua_resume           = lua_resume;
+module.exports.lua_yield            = lua_yield;
+module.exports.lua_yieldk           = lua_yieldk;
 module.exports.moveresults          = moveresults;
 module.exports.nil                  = nil;
 module.exports.stackerror           = stackerror;
diff --git a/src/lfunc.js b/src/lfunc.js
index 3b3c8ce..227606d 100644
--- a/src/lfunc.js
+++ b/src/lfunc.js
@@ -1,6 +1,8 @@
 /*jshint esversion: 6 */
 "use strict";
-const assert = require('assert');
+const assert  = require('assert');
+
+const lobject = require('./lobject.js');
 
 class Proto {
 
@@ -53,6 +55,15 @@ class UpVal {
 
 }
 
+const luaF_newLclosure = function(L, n) {
+    let c = new lobject.LClosure();
+    c.p = null;
+    c.nupvalues = n;
+    while (n--) c.upvals[n] = null;
+    return c;
+};
+
+
 const findupval = function(L, level) {
     let pp = L.openupval;
     
@@ -91,12 +102,16 @@ const luaF_close = function(L, level) {
     }
 };
 
+/*
+** fill a closure with new closed upvalues
+*/
 const luaF_initupvals = function(L, cl) {
     for (let i = 0; i < cl.nupvalues; i++) {
         let uv = new UpVal(L);
         uv.refcount = 1;
         uv.u.value = null;
         uv.v = uv.u.value;
+        cl.upvals[i] = uv;
     }
 };
 
@@ -108,7 +123,7 @@ const luaF_getlocalname = function(f, local_number, pc) {
     for (let i = 0; i < f.locvars.length && f.locvars[i].startpc <= pc; i++) {
         if (pc < f.locvars[i].endpc) {  /* is variable active? */
             local_number--;
-            if (local_number == 0)
+            if (local_number === 0)
                 return f.locvars[i].varname;
         }
     }
@@ -116,10 +131,11 @@ const luaF_getlocalname = function(f, local_number, pc) {
 }
 
 
+module.exports.MAXUPVAL          = 255;
 module.exports.Proto             = Proto;
 module.exports.UpVal             = UpVal;
 module.exports.findupval         = findupval;
 module.exports.luaF_close        = luaF_close;
-module.exports.MAXUPVAL          = 255;
+module.exports.luaF_getlocalname = luaF_getlocalname
 module.exports.luaF_initupvals   = luaF_initupvals;
-module.exports.luaF_getlocalname = luaF_getlocalname
\ No newline at end of file
+module.exports.luaF_newLclosure  = luaF_newLclosure;
\ No newline at end of file
diff --git a/src/linit.js b/src/linit.js
index 36c0121..b926683 100644
--- a/src/linit.js
+++ b/src/linit.js
@@ -1,4 +1,3 @@
-/* jshint esversion: 6 */
 "use strict";
 
 const assert = require('assert');
diff --git a/src/ljstype.js b/src/ljstype.js
new file mode 100644
index 0000000..a92c8d0
--- /dev/null
+++ b/src/ljstype.js
@@ -0,0 +1,29 @@
+"use strict";
+
+const assert = require('assert');
+
+const lisdigit = function(c) {
+    return /^\d$/.test(c.charAt(0));
+};
+
+const lisxdigit = function(c) {
+    return /^[0-9a-fA-F]$/.test(c.charAt(0));
+};
+
+const lisspace = function(c) {
+    return /^\s$/.test(c.charAt(0));
+};
+
+const lislalpha = function(c) {
+    return /^[_a-zA-z]$/.test(c.charAt(0));
+};
+
+const lislalnum = function(c) {
+    return /^[_a-zA-z0-9]$/.test(c.charAt(0));
+};
+
+module.exports.lisdigit   = lisdigit;
+module.exports.lislalnum  = lislalnum;
+module.exports.lislalpha  = lislalpha;
+module.exports.lisspace   = lisspace;
+module.exports.lisxdigit  = lisxdigit;
\ No newline at end of file
diff --git a/src/llex.js b/src/llex.js
new file mode 100644
index 0000000..63a1fbb
--- /dev/null
+++ b/src/llex.js
@@ -0,0 +1,609 @@
+"use strict";
+
+const DataView = require('buffer-dataview');
+const assert   = require('assert');
+
+const lapi     = require('./lapi.js');
+const lauxlib  = require('./lauxlib.js');
+const ldebug   = require('./ldebug.js');
+const ldo      = require('./ldo.js');
+const ljstype  = require('./ljstype');
+const lobject  = require('./lobject');
+const lua      = require('./lua.js');
+const TValue   = lobject.TValue;
+const CT       = lua.constant_types;
+const TS       = lua.thread_status;
+
+const FIRST_RESERVED = 257;
+
+const RESERVED = {
+    /* terminal symbols denoted by reserved words */
+    TK_AND:      FIRST_RESERVED,
+    TK_BREAK:    FIRST_RESERVED + 1,
+    TK_DO:       FIRST_RESERVED + 2,
+    TK_ELSE:     FIRST_RESERVED + 3,
+    TK_ELSEIF:   FIRST_RESERVED + 4,
+    TK_END:      FIRST_RESERVED + 5,
+    TK_FALSE:    FIRST_RESERVED + 6,
+    TK_FOR:      FIRST_RESERVED + 7,
+    TK_FUNCTION: FIRST_RESERVED + 8,
+    TK_GOTO:     FIRST_RESERVED + 9,
+    TK_IF:       FIRST_RESERVED + 10,
+    TK_IN:       FIRST_RESERVED + 11,
+    TK_LOCAL:    FIRST_RESERVED + 12,
+    TK_NIL:      FIRST_RESERVED + 13,
+    TK_NOT:      FIRST_RESERVED + 14,
+    TK_OR:       FIRST_RESERVED + 15,
+    TK_REPEAT:   FIRST_RESERVED + 16,
+    TK_RETURN:   FIRST_RESERVED + 17,
+    TK_THEN:     FIRST_RESERVED + 18,
+    TK_TRUE:     FIRST_RESERVED + 19,
+    TK_UNTIL:    FIRST_RESERVED + 20,
+    TK_WHILE:    FIRST_RESERVED + 21,
+    /* other terminal symbols */
+    TK_IDIV:     FIRST_RESERVED + 22,
+    TK_CONCAT:   FIRST_RESERVED + 23,
+    TK_DOTS:     FIRST_RESERVED + 24,
+    TK_EQ:       FIRST_RESERVED + 25,
+    TK_GE:       FIRST_RESERVED + 26,
+    TK_LE:       FIRST_RESERVED + 27,
+    TK_NE:       FIRST_RESERVED + 28,
+    TK_SHL:      FIRST_RESERVED + 29,
+    TK_SHR:      FIRST_RESERVED + 30,
+    TK_DBCOLON:  FIRST_RESERVED + 31,
+    TK_EOS:      FIRST_RESERVED + 32,
+    TK_FLT:      FIRST_RESERVED + 33,
+    TK_INT:      FIRST_RESERVED + 34,
+    TK_NAME:     FIRST_RESERVED + 35,
+    TK_STRING:   FIRST_RESERVED + 36
+};
+
+const R = RESERVED;
+
+const luaX_tokens = [
+    "and", "break", "do", "else", "elseif",
+    "end", "false", "for", "function", "goto", "if",
+    "in", "local", "nil", "not", "or", "repeat",
+    "return", "then", "true", "until", "while",
+    "//", "..", "...", "==", ">=", "<=", "~=",
+    "<<", ">>", "::", "<eof>",
+    "<number>", "<integer>", "<name>", "<string>"
+];
+
+const NUM_RESERVED = Object.keys(RESERVED).length;
+
+class MBuffer {
+    constructor(data) {
+        this.buffer = typeof data === "string" ? data.split('') : (data ? data : []);
+        this.n = this.buffer instanceof DataView ? this.buffer.byteLength : this.buffer.length;
+        this.off = 0;
+    }
+
+    getc() {
+        if (this.buffer instanceof DataView)
+            return this.n-- > 0 ? this.buffer.getUint8(this.off++, true) : -1;
+
+        return this.n-- > 0 ? this.buffer[this.off++] : -1;
+    }
+}
+
+class SemInfo {
+    constructor() {
+        this.r = NaN;
+        this.i = NaN;
+        this.ts = null;
+    }
+}
+
+class Token {
+    constructor() {
+        this.token = NaN;
+        this.seminfo = new SemInfo();
+    }
+}
+
+/* state of the lexer plus state of the parser when shared by all
+   functions */
+class LexState {
+    constructor() {
+        this.current = NaN;  /* current character (charint) */
+        this.linenumber = NaN;  /* input line counter */
+        this.lastline = NaN;  /* line of last token 'consumed' */
+        this.t = new Token();  /* current token */
+        this.lookahead = new Token();  /* look ahead token */
+        this.fs = null;  /* current function (parser) */
+        this.L = null;
+        this.z = new MBuffer();
+        this.buff = new MBuffer();  /* buffer for tokens */
+        this.h = null;  /* to avoid collection/reuse strings */
+        this.dyd = null;  /* dynamic structures used by the parser */
+        this.source = null;  /* current source name */
+        this.envn = null;  /* environment variable name */
+    }
+}
+
+const save = function(ls, c) {
+    let b = ls.buff;
+    if (b.n + 1 > b.buffer.length) {
+        if (b.buffer.length >= Number.MAX_SAFE_INTEGER/2)
+            lexerror(ls, "lexical element too long", 0);
+    }
+    b.buffer[b.n++] = c;
+};
+
+const luaX_token2str = function(ls, token) {
+    if (token < FIRST_RESERVED) {  /* single-byte symbols? */
+        return `'${String.fromCharCode(token)}'`;
+    } else {
+        let s = luaX_tokens[token - FIRST_RESERVED];
+        if (token < R.TK_EOS)  /* fixed format (symbols and reserved words)? */
+            return `'${s}'`;
+        else  /* names, strings, and numerals */
+            return s;
+    }
+};
+
+const currIsNewline = function(ls) {
+    return ls.current === '\n' || ls.current === '\r';
+};
+
+const next = function(ls) {
+    ls.current = ls.z.getc();
+};
+
+const save_and_next = function(ls) {
+    save(ls, ls.current);
+    next(ls);
+};
+
+/*
+** increment line number and skips newline sequence (any of
+** \n, \r, \n\r, or \r\n)
+*/
+const inclinenumber = function(ls) {
+    let old = ls.current;
+    assert(currIsNewline(ls));
+    next(ls);  /* skip '\n' or '\r' */
+    if (currIsNewline(ls) && ls.current !== old)
+        next(ls);  /* skip '\n\r' or '\r\n' */
+    if (++ls.linenumber >= Number.MAX_SAFE_INTEGER)
+        lexerror(ls, "chunk has too many lines", 0);
+};
+
+const luaX_setinput = function(L, ls, z, source, firstchar) {
+    ls.t = {
+        token: 0,
+        seminfo: {
+            i: NaN,
+            r: NaN,
+            ts: null
+        }
+    };
+    ls.L = L;
+    ls.current = firstchar;
+    ls.lookahead = {
+        token: R.TK_EOS,
+        seminfo: {
+            i: NaN,
+            r: NaN,
+            ts: null
+        }
+    };
+    ls.z = z;
+    ls.fs = null;
+    ls.linenumber = 1;
+    ls.lastline = 1;
+    ls.source = source;
+    ls.envn = new TValue(CT.LUA_TLNGSTR, "_ENV");
+};
+
+const check_next1 = function(ls, c) {
+    if (ls.current === c) {
+        next(ls);
+        return true;
+    }
+    
+    return false;
+};
+
+/*
+** Check whether current char is in set 'set' (with two chars) and
+** saves it
+*/
+const check_next2 = function(ls, set) {
+    if (ls.current === set.charAt(0) || ls.current === set.charAt(1)) {
+        save_and_next(ls);
+        return true;
+    }
+
+    return false;
+};
+
+const read_numeral = function(ls, seminfo) {
+    let expo = "Ee";
+    let first = ls.current;
+    assert(ljstype.lisdigit(ls.current));
+    save_and_next(ls);
+    if (first === '0' && check_next2(ls, "xX"))  /* hexadecimal? */
+        expo = "Pp";
+
+    for (;;) {
+        if (check_next2(ls, expo))  /* exponent part? */
+            check_next2(ls, "-+");  /* optional exponent sign */
+        if (ljstype.lisxdigit(ls.current))
+            save_and_next(ls);
+        else if (ls.current === '.')
+            save_and_next(ls);
+        else break;
+    }
+
+    save(ls, '\0');
+
+    let obj = lobject.luaO_str2num(ls.buff.buffer);
+    if (obj === false)  /* format error? */
+        lexerror(ls, "malformed number", R.TK_FLT);
+    if (obj.ttisinteger()) {
+        seminfo.i = obj.value;
+        return R.TK_INT;
+    } else {
+        assert(obj.ttisfloat());
+        seminfo.r = obj.value;
+        return R.TK_FLT;
+    }
+};
+
+const txtToken = function(ls, token) {
+    switch (token) {
+        case R.TK_NAME: case R.TK_STRING:
+        case R.TK_FLT: case R.TK_INT:
+            save(ls, '\0');
+            return `'${ls.buff.buffer.join('')}'`;
+        default:
+            return luaX_token2str(ls, token);
+    }
+};
+
+const lexerror = function(ls, msg, token) {
+    msg = ldebug.luaG_addinfo(ls.L, msg, ls.source, ls.linenumber);
+    if (token)
+        lapi.lua_pushstring(ls.L, `${msg} near ${txtToken(ls, token)}`);
+    ldo.luaD_throw(ls.L, TS.LUA_ERRSYNTAX);
+};
+
+const luaX_syntaxerror = function(ls, msg) {
+    lexerror(ls, msg, ls.t.token);
+};
+
+/*
+** skip a sequence '[=*[' or ']=*]'; if sequence is well formed, return
+** its number of '='s; otherwise, return a negative number (-1 iff there
+** are no '='s after initial bracket)
+*/
+const skip_sep = function(ls) {
+    let count = 0;
+    let s = ls.current;
+    assert(s === '[' || s === ']');
+    save_and_next(ls);
+    while (ls.current === '=') {
+        save_and_next(ls);
+        count++;
+    }
+    return ls.current === s ? count : (-count) - 1;
+};
+
+const read_long_string = function(ls, seminfo, sep) {
+    let line = ls.linenumber;  /* initial line (for error message) */
+    save_and_next(ls);  /* skip 2nd '[' */
+
+    if (currIsNewline(ls))  /* string starts with a newline? */
+        inclinenumber(ls);  /* skip it */
+
+    let skip = false;
+    for (; !skip ;) {
+        switch (ls.current) {
+            case -1: {  /* error */
+                let what = seminfo ? "string" : "comment";
+                let msg = `unfinished long ${what} (starting at line ${line})`;
+                lexerror(ls, msg, R.TK_EOS);
+                break;
+            }
+            case ']': {
+                if (skip_sep(ls) === sep) {
+                    save_and_next(ls);  /* skip 2nd ']' */
+                    skip = true;
+                }
+                break;
+            }
+            case '\n': case '\r': {
+                save(ls, '\n');
+                inclinenumber(ls);
+                if (!seminfo) {
+                    ls.buff.n = 0;
+                    ls.buff.buffer = [];
+                }
+                break;
+            }
+            default: {
+                if (seminfo) save_and_next(ls);
+                else next(ls);
+            }
+        }
+    }
+
+    if (seminfo)
+        seminfo.ts = new TValue(CT.LUA_TLNGSTR, ls.buff.buffer.slice(2 + sep).join(''));
+};
+
+const esccheck = function(ls, c, msg) {
+    if (!c) {
+        if (ls.current !== -1)
+            save_and_next(ls);  /* add current to buffer for error message */
+        lexerror(ls, msg, R.TK_STRING);
+    }
+};
+
+const gethexa = function(ls) {
+    save_and_next(ls);
+    esccheck(ls, ljstype.lisxdigit(ls.current), "hexadecimal digit expected");
+    return lobject.luaO_hexavalue(ls.current);
+};
+
+const readhexaesc = function(ls) {
+    let r = gethexa(ls);
+    r = (r << 4) + gethexa(ls);
+    ls.buff.n -= 2;  /* remove saved chars from buffer */
+    return r;
+};
+
+const readutf8desc = function(ls) {
+    let i = 4;  /* chars to be removed: '\', 'u', '{', and first digit */
+    save_and_next(ls);  /* skip 'u' */
+    esccheck(ls, ls.current === '{', "missing '{'");
+    let r = gethexa(ls);  /* must have at least one digit */
+
+    save_and_next(ls);
+    while (ljstype.lisxdigit(ls.current)) {
+        i++;
+        r = (r << 4) + lobject.luaO_hexavalue(ls.current);
+        esccheck(ls, r <= 0x10FFFF, "UTF-8 value too large");
+        save_and_next(ls);
+    }
+    esccheck(ls, ls.current === '}', "missing '}'");
+    next(ls);  /* skip '}' */
+    ls.buff.n -= i;  /* remove saved chars from buffer */
+    return r;
+};
+
+const utf8esc = function(ls) {
+    let buff = new Array(lobject.UTF8BUFFSZ);
+    let n = lobject.luaO_utf8esc(buff, readutf8desc(ls));
+    for (; n > 0; n--)  /* add 'buff' to string */
+        save(ls, buff[lobject.UTF8BUFFSZ - n]);
+};
+
+const readdecesc = function(ls) {
+    let r = 0;  /* result accumulator */
+    let i;
+    for (i = 0; i < 3 && ljstype.lisdigit(ls.current); i++) {  /* read up to 3 digits */
+        r = 10 * r + parseInt(ls.current);
+        save_and_next(ls);
+    }
+    esccheck(ls, r <= 255, "decimal escape too large");
+    ls.buff.n -= i;  /* remove read digits from buffer */
+    return r;
+};
+
+const read_string = function(ls, del, seminfo) {
+    save_and_next(ls);  /* keep delimiter (for error messages) */
+
+    while (ls.current !== del) {
+        switch (ls.current) {
+            case -1:
+                lexerror(ls, "unfinished string", R.TK_EOS);
+                break;
+            case '\n':
+            case '\r':
+                lexerror(ls, "unfinished string", R.TK_STRING);
+                break;
+            case '\\': {  /* escape sequences */
+                save_and_next(ls);  /* keep '\\' for error messages */
+                let will;
+                let c;
+                switch(ls.current) {
+                    case 'a': c = '\a'; will = 'read_save'; break;
+                    case 'b': c = '\b'; will = 'read_save'; break;
+                    case 'f': c = '\f'; will = 'read_save'; break;
+                    case 'n': c = '\n'; will = 'read_save'; break;
+                    case 'r': c = '\r'; will = 'read_save'; break;
+                    case 't': c = '\t'; will = 'read_save'; break;
+                    case 'v': c = '\v'; will = 'read_save'; break;
+                    case 'x': c = readhexaesc(ls); will = 'read_save'; break;
+                    case 'u': utf8esc(ls); will = 'read_save'; break;
+                    case '\n': case '\r':
+                        inclinenumber(ls); c = '\n'; will = 'read_save'; break;
+                    case '\\': case '\"': case '\'':
+                        c = ls.current; will = 'read_save'; break;
+                    case -1: will = 'read_save'; break;  /* will raise an error next loop */
+                    case 'z': {  /* zap following span of spaces */
+                        ls.buff.n -= 1;  /* remove '\\' */
+                        next(ls);  /* skip the 'z' */
+                        while (ljstype.lisspace(ls.current)) {
+                            if (currIsNewline(ls)) inclinenumber(ls);
+                            else next(ls);
+                        }
+                        will = 'no_save'; break;
+                    }
+                    default: {
+                        esccheck(ls, ljstype.lisdigit(ls.current), "invalid escape sequence");
+                        c = readdecesc(ls);  /* digital escape '\ddd' */
+                        will = 'only_save'; break;
+                    }
+                }
+
+                if (will === 'read_save')
+                    next(ls);
+                else if (will === 'only_save') {
+                    ls.buff.n -= 1;  /* remove '\\' */
+                    save(ls, c);
+                } else if (will === 'no_save')
+                    break;
+            }
+            default:
+                save_and_next(ls);
+        }
+    }
+    save_and_next(ls);  /* skip delimiter */
+    seminfo.ts = new TValue(CT.LUA_TLNGSTR, ls.buff.buffer.slice(1, ls.buff.buffer.length-1).join(''));
+};
+
+const isreserved = function(w) {
+    return luaX_tokens.slice(0, 22).indexOf(w) >= 0;
+};
+
+const llex = function(ls, seminfo) {
+    ls.buff.n = 0;
+    ls.buff.buffer = [];
+
+    for (;;) {
+        switch (ls.current) {
+            case '\n': case '\r': {  /* line breaks */
+                inclinenumber(ls);
+                break;
+            }
+            case ' ': case '\f': case '\t': case '\v': {  /* spaces */
+                next(ls);
+                break;
+            }
+            case '-': {  /* '-' or '--' (comment) */
+                next(ls);
+                if (ls.current !== '-') return '-';
+                /* else is a comment */
+                next(ls);
+                if (ls.current === '[') {  /* long comment? */
+                    let sep = skip_sep(ls);
+                    ls.buff.n = 0;  /* 'skip_sep' may dirty the buffer */
+                    ls.buff.buffer = [];
+                    if (sep >= 0) {
+                        read_long_string(ls, null, sep);  /* skip long comment */
+                        ls.buff.n = 0;  /* previous call may dirty the buff. */
+                        ls.buff.buffer = [];
+                        break;
+                    }
+                }
+
+                /* else short comment */
+                while (!currIsNewline(ls) && ls.current !== -1)
+                    next(ls);  /* skip until end of line (or end of file) */
+                break;
+            }
+            case '[': {  /* long string or simply '[' */
+                let sep = skip_sep(ls);
+                if (sep.charCodeAt(0) >= 0) {
+                    read_long_string(ls, seminfo, sep);
+                    return R.TK_STRING;
+                } else if (sep !== -1)  /* '[=...' missing second bracket */
+                    lexerror(ls, "invalid long string delimiter", R.TK_STRING);
+                return '[';
+            }
+            case '=': {
+                next(ls);
+                if (check_next1(ls, '=')) return R.TK_EQ;
+                else return '=';
+            }
+            case '<': {
+                next(ls);
+                if (check_next1(ls, '=')) return R.TK_LE;
+                else if (check_next1(ls, '<')) return R.TK_SHL;
+                else return '<';
+            }
+            case '>': {
+                next(ls);
+                if (check_next1(ls, '=')) return R.TK_GE;
+                else if (check_next1(ls, '>')) return R.TK_SHR;
+                else return '>';
+            }
+            case '/': {
+                next(ls);
+                if (check_next1(ls, '/')) return R.TK_IDIV;
+                else return '/';
+            }
+            case '~': {
+                next(ls);
+                if (check_next1(ls, '=')) return R.TK_NE;
+                else return '~';
+            }
+            case ':': {
+                next(ls);
+                if (check_next1(ls, ':')) return R.TK_DBCOLON;
+                else return ':';
+            }
+            case '"': case '\'': {  /* short literal strings */
+                read_string(ls, ls.current, seminfo);
+                return R.TK_STRING;
+            }
+            case '.': {  /* '.', '..', '...', or number */
+                save_and_next(ls);
+                if (check_next1(ls, '.')) {
+                    if (check_next1(ls, '.'))
+                        return R.TK_DOTS;   /* '...' */
+                    else return R.TK_CONCAT;   /* '..' */
+                }
+                else if (!ljstype.lisdigit(ls.current)) return '.';
+                else return read_numeral(ls, seminfo);
+            }
+            case '0': case '1': case '2': case '3': case '4':
+            case '5': case '6': case '7': case '8': case '9': {
+                return read_numeral(ls, seminfo);
+            }
+            case -1: {
+                return R.TK_EOS;
+            }
+            default: {
+                if (ljstype.lislalpha(ls.current)) {  /* identifier or reserved word? */
+                    do {
+                        save_and_next(ls);
+                    } while (ljstype.lislalnum(ls.current));
+
+                    let ts = new TValue(CT.LUA_TLNGSTR, ls.buff.buffer.join(''));
+                    seminfo.ts = ts;
+                    let kidx = luaX_tokens.slice(0, 22).indexOf(ts.value);
+                    if (kidx >= 0)  /* reserved word? */
+                        return kidx + FIRST_RESERVED;
+                    else
+                        return R.TK_NAME;
+                } else {  /* single-char tokens (+ - / ...) */
+                    let c = ls.current;
+                    next(ls);
+                    return c;
+                }
+            }
+        }
+    }
+};
+
+const luaX_next = function(ls) {
+    ls.lastline = ls.linenumber;
+    if (ls.lookahead.token !== R.TK_EOS) {  /* is there a look-ahead token? */
+        ls.t = ls.lookahead;  /* use this one */
+        ls.lookahead.token = R.TK_EOS;  /* and discharge it */
+    } else
+        ls.t.token = llex(ls, ls.t.seminfo);  /* read next token */
+};
+
+const luaX_lookahead = function(ls) {
+    assert(ls.lookahead.token === R.TK_EOS);
+    ls.lookahead.token = llex(ls. ls.lookahead.seminfo);
+    return ls.lookahead.token;
+};
+
+module.exports.FIRST_RESERVED   = FIRST_RESERVED;
+module.exports.LexState         = LexState;
+module.exports.MBuffer          = MBuffer;
+module.exports.RESERVED         = RESERVED;
+module.exports.isreserved       = isreserved;
+module.exports.luaX_lookahead   = luaX_lookahead;
+module.exports.luaX_next        = luaX_next;
+module.exports.luaX_setinput    = luaX_setinput;
+module.exports.luaX_syntaxerror = luaX_syntaxerror;
+module.exports.luaX_token2str   = luaX_token2str;
+module.exports.luaX_tokens      = luaX_tokens;
\ No newline at end of file
diff --git a/src/lmathlib.js b/src/lmathlib.js
index 54bdc46..55f8416 100644
--- a/src/lmathlib.js
+++ b/src/lmathlib.js
@@ -1,4 +1,3 @@
-/* jshint esversion: 6 */
 "use strict";
 
 const assert     = require('assert');
diff --git a/src/lobject.js b/src/lobject.js
index 086af00..bd234a1 100644
--- a/src/lobject.js
+++ b/src/lobject.js
@@ -1,8 +1,12 @@
-/*jshint esversion: 6 */
+ /*jshint esversion: 6 */
 "use strict";
 
-const CT    = require('./lua.js').constant_types;
-const UpVal = require('./lfunc.js').UpVal;
+const assert = require('assert');
+
+const ljstype = require('./ljstype.js');
+const lua     = require('./lua.js');
+const CT      = lua.constant_types;
+const UpVal   = require('./lfunc.js').UpVal;
 
 class TValue {
 
@@ -122,6 +126,7 @@ class Table extends TValue {
         // Those lua values are used by value, others by reference
         if (key instanceof TValue
             && [CT.LUA_TNIL,
+                CT.LUA_TBOOLEAN,
                 CT.LUA_TSTRING,
                 CT.LUA_TSHRSTR,
                 CT.LUA_TLNGSTR,
@@ -199,6 +204,18 @@ class CClosure extends TValue {
 
 }
 
+/*
+** Description of a local variable for function prototypes
+** (used for debug information)
+*/
+class LocVar {
+    constructor() {
+        this.varname = null;
+        this.startpc = NaN;  /* first point where variable is active */
+        this.endpc = NaN;    /* first point where variable is dead */
+    }
+}
+
 const RETS = "...";
 const PRE  = "[string \"";
 const POS  = "\"]";
@@ -223,7 +240,7 @@ const luaO_chunkid = function(source, bufflen) {
         let nli = source.indexOf('\n');  /* find first new line (if any) */
         let nl = nli ? source.slice(nli) : null;
         out = `${PRE}`;  /* add prefix */
-        bufflen -= PRE.length - RETS.length; - POS.length + 1;  /* save space for prefix+suffix+'\0' */
+        bufflen -= PRE.length + RETS.length + POS.length + 1;  /* save space for prefix+suffix+'\0' */
         if (l < bufflen && nl === null) {  /* small one-line source? */
             out += `${source}`;  /* keep it */
         } else {
@@ -237,8 +254,170 @@ const luaO_chunkid = function(source, bufflen) {
     return out;
 };
 
-module.exports.LClosure     = LClosure;
-module.exports.CClosure     = CClosure;
-module.exports.TValue       = TValue;
-module.exports.Table        = Table;
-module.exports.luaO_chunkid = luaO_chunkid;
\ No newline at end of file
+const luaO_hexavalue = function(c) {
+    if (ljstype.lisdigit(c)) return c.charCodeAt(0) - '0'.charCodeAt(0);
+    else return (c.toLowerCase().charCodeAt(0) - 'a'.charCodeAt(0)) + 10;
+};
+
+const UTF8BUFFSZ = 8;
+
+const luaO_utf8desc = function(buff, x) {
+    let n = 1;  /* number of bytes put in buffer (backwards) */
+    assert(x <= 0x10FFFF);
+    if (x < 0x80)  /* ascii? */
+        buff[UTF8BUFFSZ - 1] = String.fromCharCode(x);
+    else {  /* need continuation bytes */
+        let mfb = 0x3f;  /* maximum that fits in first byte */
+        do {
+            buff[UTF8BUFFSZ - (n++)] = String.fromCharCode(0x80 | (x & 0x3f));
+            x >>= 6;  /* remove added bits */
+            mfb >>= 1;  /* now there is one less bit available in first byte */
+        } while (x > mfb);  /* still needs continuation byte? */
+        buff[UTF8BUFFSZ - n] = String.fromCharCode((~mfb << 1) | x);  /* add first byte */
+    }
+    return n;
+};
+
+const l_str2dloc = function(s, result, mode) {
+    result[0] = mode === 'x' ? parseInt(s, '16') : parseInt(s);
+    if (isNaN(result[0])) return null;  /* nothing recognized? */
+    while (ljstype.lisspace(result[0])) result[0] = result[0].slice(1);  /* skip trailing spaces */
+    return result[0] === '\0' ? result : null;  /* OK if no trailing characters */
+};
+
+const l_str2d = function(s) {
+    let result = [null, null];
+    let pidx = /[.xXnN]/g.exec(s).index;
+    let pmode = pidx ? s.slice(pidx) : null;
+    let mode = pmode ? pmode.toLowerCase() : 0;
+    if (mode === 'n')  /* reject 'inf' and 'nan' */
+        return null;
+    let end = l_str2dloc(s, result, mode)[0];  /* try to convert */
+    if (end === null) {   /* failed? may be a different locale */
+        throw new Error("Locale not available to handle number"); // TODO
+    }
+    return [end, result[1]];
+};
+
+const MAXBY10  = Number.MAX_SAFE_INTEGER / 10;
+const MAXLASTD = Number.MAX_SAFE_INTEGER % 10;
+
+const l_str2int = function(s) {
+    let result = [null, null];
+    let a = 0;
+    let empty = true;
+    let neg;
+
+    while (ljstype.lisspace(s[0])) s = s.slice(1);  /* skip initial spaces */
+    neg = s[0] === '-';
+
+    if (neg || s[0] === '+')
+        s = s.slice(1);
+
+    if (s[0] === '0' && (s[1] === 'x' || s[1] === 'X')) {  /* hex? */
+        s = s.slice(2);  /* skip '0x' */
+
+        for (; ljstype.lisxdigit(s[0]); s = s.slice(1)) {
+            a = a * 16 + luaO_hexavalue(s);
+            empty = false;
+        }
+    } else {  /* decimal */
+        for (; ljstype.lisdigit(s[0]); s = s.slice(1)) {
+            let d = parseInt(s[0]);
+            if (a >= MAXBY10 && (a > MAXBY10 || d > MAXLASTD + neg))  /* overflow? */
+                return null;  /* do not accept it (as integer) */
+            a = a * 10 + d;
+            empty = false;
+        }
+    }
+
+    while (ljstype.lisspace(s[0])) s = s.slice(1);  /* skip trailing spaces */
+
+    if (empty)/* TODO: || s[0] !== "") */ return null;  /* something wrong in the numeral */
+    else {
+        result[1] = neg ? -a : a;
+        result[0] = s;
+        return result;
+    }
+};
+
+const luaO_str2num = function(s) {
+    let s2i = l_str2int(s);
+    let e = s2i[0];
+    let i = s2i[1];
+
+    if (e !== null) {   /* try as an integer */
+        return new TValue(CT.LUA_TNUMINT, i);
+    } else {   /* else try as a float */
+        s2i = l_str2d(s);
+        e = s2i[0];
+        i = s2i[1];
+
+        if (e !== null) {
+            return new TValue(CT.LUA_TNUMFLT, i);
+        } else
+            return false;  /* conversion failed */
+    }
+};
+
+/*
+** converts an integer to a "floating point byte", represented as
+** (eeeeexxx), where the real value is (1xxx) * 2^(eeeee - 1) if
+** eeeee !== 0 and (xxx) otherwise.
+*/
+const luaO_int2fb = function(x) {
+    let e = 0;  /* exponent */
+    if (x < 8) return x;
+    while (x >= (8 << 4)) {  /* coarse steps */
+        x = (x + 0xf) >> 4;  /* x = ceil(x / 16) */
+        e += 4;
+    }
+    while (x >= (8 << 1)) {  /* fine steps */
+        x = (x + 1) >> 1;  /* x = ceil(x / 2) */
+        e++;
+    }
+    return ((e+1) << 3) | (x - 8);
+};
+
+const intarith = function(L, op, v1, v2) {
+    switch (op) {
+        case lua.LUA_OPADD:  return (v1 + v2)|0;
+        case lua.LUA_OPSUB:  return (v1 - v2)|0;
+        case lua.LUA_OPMUL:  return (v1 * v2)|0;
+        case lua.LUA_OPMOD:  return (v1 % v2)|0;
+        case lua.LUA_OPIDIV: return (v1 / v2)|0;
+        case lua.LUA_OPBAND: return (v1 & v2)|0;
+        case lua.LUA_OPBOR:  return (v1 | v2)|0;
+        case lua.LUA_OPBXOR: return (v1 ^ v2)|0;
+        case lua.LUA_OPSHL:  return (v1 << v2)|0;
+        case lua.LUA_OPSHR:  return (v1 >> v2)|0;
+        case lua.LUA_OPUNM:  return (-v1)|0;
+        case lua.LUA_OPBNOT: return (~v1)|0;
+    }
+};
+
+
+const numarith = function(L, op, v1, v2) {
+    switch (op) {
+        case lua.LUA_OPADD:  return v1 + v2;
+        case lua.LUA_OPSUB:  return v1 - v2;
+        case lua.LUA_OPMUL:  return v1 * v2;
+        case lua.LUA_OPDIV:  return v1 / v2;
+        case lua.LUA_OPPOW:  return Math.pow(v1, v2);
+        case lua.LUA_OPIDIV: return (v1 / v2)|0;
+        case lua.LUA_OPUNM:  return -v1;
+        case lua.LUA_OPMOD:  return v1 % v2;
+    }
+};
+
+module.exports.CClosure       = CClosure;
+module.exports.LClosure       = LClosure;
+module.exports.LocVar         = LocVar;
+module.exports.TValue         = TValue;
+module.exports.Table          = Table;
+module.exports.UTF8BUFFSZ     = UTF8BUFFSZ;
+module.exports.luaO_chunkid   = luaO_chunkid;
+module.exports.luaO_hexavalue = luaO_hexavalue;
+module.exports.luaO_int2fb    = luaO_int2fb;
+module.exports.luaO_str2num   = luaO_str2num;
+module.exports.luaO_utf8desc  = luaO_utf8desc;
\ No newline at end of file
diff --git a/src/lopcodes.js b/src/lopcodes.js
index 5723abb..bfcd993 100644
--- a/src/lopcodes.js
+++ b/src/lopcodes.js
@@ -51,6 +51,56 @@ const OpCodes = [
     "OP_EXTRAARG"
 ];
 
+const OpCodesI = {
+    OP_MOVE:     0,
+    OP_LOADK:    1,
+    OP_LOADKX:   2,
+    OP_LOADBOOL: 3,
+    OP_LOADNIL:  4,
+    OP_GETUPVAL: 5,
+    OP_GETTABUP: 6,
+    OP_GETTABLE: 7,
+    OP_SETTABUP: 8,
+    OP_SETUPVAL: 9,
+    OP_SETTABLE: 10,
+    OP_NEWTABLE: 11,
+    OP_SELF:     12,
+    OP_ADD:      13,
+    OP_SUB:      14,
+    OP_MUL:      15,
+    OP_MOD:      16,
+    OP_POW:      17,
+    OP_DIV:      18,
+    OP_IDIV:     19,
+    OP_BAND:     20,
+    OP_BOR:      21,
+    OP_BXOR:     22,
+    OP_SHL:      23,
+    OP_SHR:      24,
+    OP_UNM:      25,
+    OP_BNOT:     26,
+    OP_NOT:      27,
+    OP_LEN:      28,
+    OP_CONCAT:   29,
+    OP_JMP:      30,
+    OP_EQ:       31,
+    OP_LT:       32,
+    OP_LE:       33,
+    OP_TEST:     34,
+    OP_TESTSET:  35,
+    OP_CALL:     36,
+    OP_TAILCALL: 37,
+    OP_RETURN:   38,
+    OP_FORLOOP:  39,
+    OP_FORPREP:  40,
+    OP_TFORCALL: 41,
+    OP_TFORLOOP: 42,
+    OP_SETLIST:  43,
+    OP_CLOSURE:  44,
+    OP_VARARG:   45,
+    OP_EXTRAARG: 46
+};
+
 /*
 ** masks for instruction properties. The format is:
 ** bits 0-1: op mode
@@ -120,10 +170,26 @@ const luaP_opmodes = [
     0 << 7 | 0 << 6 | OpArgU << 4 | OpArgU << 2 | iAx     /* OP_EXTRAARG */
 ];
 
+const getOpMode = function(m) {
+    return luaP_opmodes[m] & 3;
+};
+
+const getBMode = function(m) {
+    return (luaP_opmodes[m] >> 4) & 3;
+};
+
+const getCMode = function(m) {
+    return (luaP_opmodes[m] >> 2) & 3;
+};
+
 const testAMode = function(m) {
     return luaP_opmodes[m] & (1 << 6);
 };
 
+const testTMode = function(m) {
+    return luaP_opmodes[m] & (1 << 7);
+};
+
 const SIZE_C     = 9;
 const SIZE_B     = 9;
 const SIZE_Bx    = (SIZE_C + SIZE_B);
@@ -143,40 +209,158 @@ const MAXARG_A   = ((1 << SIZE_A) - 1);
 const MAXARG_B   = ((1 << SIZE_B) - 1);
 const MAXARG_C   = ((1 << SIZE_C) - 1);
 
+/* this bit 1 means constant (0 means register) */
 const BITRK      = (1 << (SIZE_B - 1));
 
+/*
+** invalid register that fits in 8 bits
+*/
+const NO_REG     = MAXARG_A;
+
+/* test whether value is a constant */
 const ISK = function (x) {
     return x & BITRK;
 };
 
+/* gets the index of the constant */
 const INDEXK = function (r) {
     return r & ~BITRK;
 };
 
+/* code a constant index as a RK value */
+const RKASK = function(x) {
+    return x | BITRK;
+};
+
+
+/* creates a mask with 'n' 1 bits at position 'p' */
+const MASK1 = function(n, p) {
+    return ((~((~0)<<(n)))<<(p));
+};
+
+/* creates a mask with 'n' 0 bits at position 'p' */
+const MASK0 = function(n, p) {
+    return (~MASK1(n, p));
+};
+
+const setarg = function(i, v, pos, size) {
+    i.code = (i.code & MASK0(size, pos)) | ((v << pos) & MASK1(size, pos));
+    fullins(i);
+};
+
+const SETARG_A = function(i,v) {
+    setarg(i, v, POS_A, SIZE_A);
+};
+
+const SETARG_B = function(i,v) {
+    setarg(i, v, POS_B, SIZE_B);
+};
+
+const SETARG_C = function(i,v) {
+    setarg(i, v, POS_C, SIZE_C);
+};
+
+const SETARG_Bx = function(i,v) {
+    setarg(i, v, POS_Bx, SIZE_Bx);
+};
+
+const SETARG_Ax = function(i,v) {
+    setarg(i, v, POS_Ax, SIZE_Ax);
+};
+
+const SETARG_sBx = function(i, b) {
+    SETARG_Bx(i, b + MAXARG_sBx);
+};
+
+/*
+** Pre-calculate all possible part of the instruction
+*/
+const fullins = function(ins) {
+    if (typeof ins === "number") {
+        return {
+            code:   ins,
+            opcode: (ins >> POS_OP) & MASK1(SIZE_OP, 0),
+            A:      (ins >> POS_A)  & MASK1(SIZE_A,  0),
+            B:      (ins >> POS_B)  & MASK1(SIZE_B,  0),
+            C:      (ins >> POS_C)  & MASK1(SIZE_C,  0),
+            Bx:     (ins >> POS_Bx) & MASK1(SIZE_Bx, 0),
+            Ax:     (ins >> POS_Ax) & MASK1(SIZE_Ax, 0),
+            sBx:    ((ins >> POS_Bx) & MASK1(SIZE_Bx, 0)) - MAXARG_sBx
+        };
+    } else {
+        let i = ins.code;
+        ins.opcode = (i >> POS_OP) & MASK1(SIZE_OP, 0);
+        ins.A      = (i >> POS_A)  & MASK1(SIZE_A,  0);
+        ins.B      = (i >> POS_B)  & MASK1(SIZE_B,  0);
+        ins.C      = (i >> POS_C)  & MASK1(SIZE_C,  0);
+        ins.Bx     = (i >> POS_Bx) & MASK1(SIZE_Bx, 0);
+        ins.Ax     = (i >> POS_Ax) & MASK1(SIZE_Ax, 0);
+        ins.sBx    = ((i >> POS_Bx) & MASK1(SIZE_Bx, 0)) - MAXARG_sBx;
+        return ins;
+    }
+};
+
+const CREATE_ABC = function(o, a, b, c) {
+    return fullins(o << POS_OP | a << POS_A | b << POS_B | c << POS_C);
+};
+
+const CREATE_ABx = function(o, a, bc) {
+    return fullins(o << POS_OP | a << POS_A | bc << POS_Bx);
+};
+
+const CREATE_Ax = function(o, a) {
+    return fullins(o << POS_OP | a << POS_Ax);
+};
+
 /* number of list items to accumulate before a SETLIST instruction */
 const LFIELDS_PER_FLUSH = 50;
 
-module.exports.OpCodes           = OpCodes;
-module.exports.SIZE_C            = SIZE_C;
-module.exports.SIZE_B            = SIZE_B;
-module.exports.SIZE_Bx           = SIZE_Bx;
-module.exports.SIZE_A            = SIZE_A;
-module.exports.SIZE_Ax           = SIZE_Ax;
-module.exports.SIZE_OP           = SIZE_OP;
-module.exports.POS_OP            = POS_OP;
-module.exports.POS_A             = POS_A;
-module.exports.POS_C             = POS_C;
-module.exports.POS_B             = POS_B;
-module.exports.POS_Bx            = POS_Bx;
-module.exports.POS_Ax            = POS_Ax;
-module.exports.MAXARG_Bx         = MAXARG_Bx;
-module.exports.MAXARG_sBx        = MAXARG_sBx;
-module.exports.MAXARG_Ax         = MAXARG_Ax;
-module.exports.MAXARG_A          = MAXARG_A;
-module.exports.MAXARG_B          = MAXARG_B;
-module.exports.MAXARG_C          = MAXARG_C;
-module.exports.BITRK             = BITRK;
-module.exports.ISK               = ISK;
-module.exports.INDEXK            = INDEXK;
-module.exports.LFIELDS_PER_FLUSH = LFIELDS_PER_FLUSH;
-module.exports.testAMode         = testAMode;
\ No newline at end of file
+module.exports.BITRK               = BITRK;
+module.exports.CREATE_ABC          = CREATE_ABC;
+module.exports.CREATE_ABx          = CREATE_ABx;
+module.exports.CREATE_Ax           = CREATE_Ax;
+module.exports.INDEXK              = INDEXK;
+module.exports.ISK                 = ISK;
+module.exports.LFIELDS_PER_FLUSH   = LFIELDS_PER_FLUSH;
+module.exports.MAXARG_A            = MAXARG_A;
+module.exports.MAXARG_Ax           = MAXARG_Ax;
+module.exports.MAXARG_B            = MAXARG_B;
+module.exports.MAXARG_Bx           = MAXARG_Bx;
+module.exports.MAXARG_C            = MAXARG_C;
+module.exports.MAXARG_sBx          = MAXARG_sBx;
+module.exports.NO_REG              = NO_REG;
+module.exports.OpArgK              = OpArgK;
+module.exports.OpArgN              = OpArgN;
+module.exports.OpArgR              = OpArgR;
+module.exports.OpArgU              = OpArgU;
+module.exports.OpCodes             = OpCodes;
+module.exports.OpCodesI            = OpCodesI;
+module.exports.POS_A               = POS_A;
+module.exports.POS_Ax              = POS_Ax;
+module.exports.POS_B               = POS_B;
+module.exports.POS_Bx              = POS_Bx;
+module.exports.POS_C               = POS_C;
+module.exports.POS_OP              = POS_OP;
+module.exports.RKASK               = RKASK;
+module.exports.SETARG_A            = SETARG_A;
+module.exports.SETARG_Ax           = SETARG_Ax;
+module.exports.SETARG_B            = SETARG_B;
+module.exports.SETARG_Bx           = SETARG_Bx;
+module.exports.SETARG_C            = SETARG_C;
+module.exports.SETARG_sBx          = SETARG_sBx;
+module.exports.SIZE_A              = SIZE_A;
+module.exports.SIZE_Ax             = SIZE_Ax;
+module.exports.SIZE_B              = SIZE_B;
+module.exports.SIZE_Bx             = SIZE_Bx;
+module.exports.SIZE_C              = SIZE_C;
+module.exports.SIZE_OP             = SIZE_OP;
+module.exports.fullins             = fullins;
+module.exports.getBMode            = getBMode;
+module.exports.getCMode            = getCMode;
+module.exports.getOpMode           = getOpMode;
+module.exports.iABC                = iABC;
+module.exports.iABx                = iABx;
+module.exports.iAsBx               = iAsBx;
+module.exports.iAx                 = iAx;
+module.exports.testAMode           = testAMode;
+module.exports.testTMode           = testTMode;
\ No newline at end of file
diff --git a/src/lparser.js b/src/lparser.js
new file mode 100644
index 0000000..1e454e0
--- /dev/null
+++ b/src/lparser.js
@@ -0,0 +1,1560 @@
+"use strict";
+
+const assert = require('assert');
+
+const lcode    = require('./lcode.js');
+const lfunc    = require('./lfunc.js');
+const llex     = require('./llex.js');
+const llimit   = require('./llimit.js');
+const lobject  = require('./lobject.js');
+const lopcode  = require('./lopcodes.js');
+const lua      = require('./lua.js');
+const BinOpr   = lcode.BinOpr;
+const OpCodesI = lopcode.OpCodesI;
+const Proto    = lfunc.Proto;
+const R        = llex.RESERVED;
+const TValue   = lobject.TValue;
+const Table    = lobject.Table;
+const UnOpr    = lcode.UnOpr;
+const UpVal    = lfunc.UpVal;
+
+const MAXVARS = 200;
+
+const hasmultret = function(k) {
+    return k === expkind.VCALL || k === expkind.VVARARG;
+};
+
+class BlockCnt {
+    constructor() {
+        this.previous = null;  /* chain */
+        this.firstlabel = NaN; /* index of first label in this block */
+        this.firstgoto = NaN;  /* index of first pending goto in this block */
+        this.nactvar = NaN;    /* # active locals outside the block */
+        this.upval = NaN;      /* true if some variable in the block is an upvalue */
+        this.isloop = NaN;     /* true if 'block' is a loop */
+    }
+}
+
+const expkind = {
+    VVOID: 0,        /* when 'expdesc' describes the last expression a list,
+                        this kind means an empty list (so, no expression) */
+    VNIL: 1,         /* constant nil */
+    VTRUE: 2,        /* constant true */
+    VFALSE: 3,       /* constant false */
+    VK: 4,           /* constant in 'k'; info = index of constant in 'k' */
+    VKFLT: 5,        /* floating constant; nval = numerical float value */
+    VKINT: 6,        /* integer constant; nval = numerical integer value */
+    VNONRELOC: 7,    /* expression has its value in a fixed register;
+                        info = result register */
+    VLOCAL: 8,       /* local variable; info = local register */
+    VUPVAL: 9,       /* upvalue variable; info = index of upvalue in 'upvalues' */
+    VINDEXED: 10,    /* indexed variable;
+                        ind.vt = whether 't' is register or upvalue;
+                        ind.t = table register or upvalue;
+                        ind.idx = key's R/K index */
+    VJMP: 11,        /* expression is a test/comparison;
+                        info = pc of corresponding jump instruction */
+    VRELOCABLE: 12,  /* expression can put result in any register;
+                        info = instruction pc */
+    VCALL: 13,       /* expression is a function call; info = instruction pc */
+    VVARARG: 14      /* vararg expression; info = instruction pc */
+};
+
+const vkisvar = function(k) {
+    return expkind.VLOCAL <= k && k <= expkind.VINDEXED;
+};
+
+const vkisinreg = function(k) {
+    return k === expkind.VNONRELOC || k === expkind.VLOCAL;
+};
+
+class expdesc {
+    constructor() {
+        this.k = NaN;
+        this.u = {
+            ival: NaN,    /* for VKINT */
+            nval: NaN,    /* for VKFLT */
+            info: NaN,    /* for generic use */
+            ind: {        /* for indexed variables (VINDEXED) */
+                idx: NaN, /* index (R/K) */
+                t: NaN,   /* table (register or upvalue) */
+                vt: NaN   /* whether 't' is register (VLOCAL) or upvalue (VUPVAL) */
+            }
+        };
+        this.t = NaN;     /* patch list of 'exit when true' */
+        this.f = NaN;     /* patch list of 'exit when false' */
+    }
+}
+
+class FuncState {
+    constructor() {
+        this.f = null;         /* current function header */
+        this.prev = null;      /* enclosing function */
+        this.ls = null;        /* lexical state */
+        this.bl = null;        /* chain of current blocks */
+        this.pc = NaN;         /* next position to code (equivalent to 'ncode') */
+        this.lasttarget = NaN; /* 'label' of last 'jump label' */
+        this.jpc = NaN;        /* list of pending jumps to 'pc' */
+        this.nk = NaN;         /* number of elements in 'k' */
+        this.np = NaN;         /* number of elements in 'p' */
+        this.firstlocal = NaN; /* index of first local var (in Dyndata array) */
+        this.nlocvars = NaN;   /* number of elements in 'f->locvars' */
+        this.nactvar = NaN;    /* number of active local variables */
+        this.nups = NaN;       /* number of upvalues */
+        this.freereg = NaN;    /* first free register */
+    }
+}
+
+    /* description of active local variable */
+class Vardesc {
+    constructor() {
+        this.idx = NaN;  /* variable index in stack */
+    }
+}
+
+
+/* description of pending goto statements and label statements */
+class Labeldesc {
+    constructor() {
+        this.name = null;  /* label identifier */
+        this.pc = NaN;  /* position in code */
+        this.line = NaN;  /* line where it appeared */
+        this.nactvar = NaN;  /* local level where it appears in current block */
+    }
+}
+
+
+/* list of labels or gotos */
+class Labellist {
+    constructor() {
+        this.arr = []; /* array */
+        this.n = NaN;  /* number of entries in use */
+        this.size = NaN;  /* array size */
+    }
+}
+
+/* dynamic structures used by the parser */
+class Dyndata {
+    constructor() {
+        this.actvar = {  /* list of active local variables */
+            arr: [],
+            n: NaN,
+            size: NaN
+        };
+        this.gt = new Labellist();
+        this.label = new Labellist();
+    }
+}
+
+const semerror = function(ls, msg) {
+    ls.t.token = 0;  /* remove "near <token>" from final message */
+    llex.luaX_syntaxerror(ls, msg);
+};
+
+const error_expected = function(ls, token) {
+    llex.luaX_syntaxerror(ls, `${llex.luaX_token2str(ls, token)} expected`);
+};
+
+const errorlimit = function(fs, limit, what) {
+    let L = fs.ls.L;
+    let line = fs.f.linedefined;
+    let where = (line === 0) ? "main function" : `function at line ${line}`;
+    let msg = `too many ${what} (limit is ${limit}) in ${where}`;
+    llex.luaX_syntaxerror(fs.ls, msg);
+};
+
+const checklimit = function(fs, v, l, what) {
+    if (v > l) errorlimit(fs, l, what);
+};
+
+const testnext = function(ls, c) {
+    if (ls.t.token === c) {
+        llex.luaX_next(ls);
+        return true;
+    }
+
+    return false;
+};
+
+const check = function(ls, c) {
+    if (ls.t.token !== c)
+        error_expected(ls, c);
+};
+
+const checknext = function(ls, c) {
+    check(ls, c);
+    llex.luaX_next(ls);
+};
+
+const check_condition = function(ls, c, msg) {
+    if (!c)
+        llex.luaX_syntaxerror(ls, msg);
+};
+
+const check_match = function(ls, what, who, where) {
+    if (!testnext(ls, what)) {
+        if (where === ls.linenumber)
+            error_expected(ls, what);
+        else
+            llex.luaX_syntaxerror(ls,
+                `${llex.luaX_token2str(ls, what)} expected (to close ${llex.luaX_token2str(ls, who)} at line ${where}`);
+    }
+};
+
+const str_checkname = function(ls) {
+    check(ls, R.TK_NAME);
+    let ts = ls.t.seminfo.ts;
+    llex.luaX_next(ls);
+    return ts;
+};
+
+const init_exp = function(e, k, i) {
+    e.f = e.t = lcode.NO_JUMP;
+    e.k = k;
+    e.u.info = i;
+};
+
+const codestring = function(ls, e, s) {
+    init_exp(e, expkind.VK, lcode.luaK_stringK(ls.fs, s));
+};
+
+const checkname = function(ls, e) {
+    codestring(ls, e, str_checkname(ls));
+};
+
+const registerlocalvar = function(ls, varname) {
+    let fs = ls.fs;
+    let f = fs.f;
+    f.locvars[fs.nlocvars] = new lobject.LocVar();
+    f.locvars[fs.nlocvars].varname = varname;
+    return fs.nlocvars++;
+};
+
+const new_localvar = function(ls, name) {
+    let fs = ls.fs;
+    let dyd = ls.dyd;
+    let reg = registerlocalvar(ls, name);
+    checklimit(fs, dyd.actvar.n + 1 - fs.firstlocal, MAXVARS, "local variables");
+    dyd.actvar.arr[dyd.actvar.n] = new Vardesc();
+    dyd.actvar.arr[dyd.actvar.n].idx = reg;
+    dyd.actvar.n++;
+};
+
+const new_localvarliteral = function(ls, name) {
+    new_localvar(ls, new TValue(lua.CT.LUA_TLNGSTR, name));
+};
+
+const getlocvar = function(fs, i) {
+    let idx = fs.ls.dyd.actvar.arr[fs.firstlocal + i].idx;
+    assert(idx < fs.nlocvars);
+    return fs.f.locvars[idx];
+};
+
+const adjustlocalvars = function(ls, nvars) {
+    let fs = ls.fs;
+    fs.nactvar = fs.nactvar + nvars;
+    for (; nvars; nvars--)
+        getlocvar(fs, fs.nactvar - nvars).startpc = fs.pc;
+};
+
+const removevars = function(fs, tolevel) {
+    fs.ls.dyd.actvar.n -= fs.nactvar - tolevel;
+    while (fs.nactvar > tolevel)
+        getlocvar(fs, --fs.nactvar).endpc = fs.pc;
+};
+
+const searchupvalue = function(fs, name) {
+    let up = fs.f.upvalues;
+    for (let i = 0; i < fs.nups; i++) {
+        if (up[i].name.value === name.value)
+            return i;
+    }
+    return -1;  /* not found */
+};
+
+const newupvalue = function(fs, name, v) {
+    let f = fs.f;
+    checklimit(fs, fs.nups + 1, lfunc.MAXUPVAL, "upvalues");
+    f.upvalues[fs.nups] = new UpVal(fs.ls.L);
+    f.upvalues[fs.nups].instack = v.k === expkind.VLOCAL;
+    f.upvalues[fs.nups].idx = v.u.info;
+    f.upvalues[fs.nups].name = name;
+    return fs.nups++;
+};
+
+const searchvar = function(fs, n) {
+    for (let i = fs.nactvar - 1; i >= 0; i--) {
+        if (n.value === getlocvar(fs, i).varname.value)
+            return i;
+    }
+
+    return -1;
+};
+
+/*
+** Mark block where variable at given level was defined
+** (to emit close instructions later).
+*/
+const markupval = function(fs, level) {
+    let bl = fs.bl;
+    while (bl.nactvar > level)
+        bl = bl.previous;
+    bl.upval = 1;
+};
+
+/*
+** Find variable with given name 'n'. If it is an upvalue, add this
+** upvalue into all intermediate functions.
+*/
+const singlevaraux = function(fs, n, vr, base) {
+    if (fs === null)  /* no more levels? */
+        init_exp(vr, expkind.VVOID, 0);  /* default is global */
+    else {
+        let v = searchvar(fs, n);  /* look up locals at current level */
+        if (v >= 0) {  /* found? */
+            init_exp(vr, expkind.VLOCAL, v);  /* variable is local */
+            if (!base)
+                markupval(fs, v);  /* local will be used as an upval */
+        } else {  /* not found as local at current level; try upvalues */
+            let idx = searchupvalue(fs, n);  /* try existing upvalues */
+            if (idx < 0) {  /* not found? */
+                singlevaraux(fs.prev, n, vr, 0);  /* try upper levels */
+                if (vr.k === expkind.VVOID)  /* not found? */
+                    return;  /* it is a global */
+                /* else was LOCAL or UPVAL */
+                idx = newupvalue(fs, n, vr);  /* will be a new upvalue */
+            }
+            init_exp(vr, expkind.VUPVAL, idx);  /* new or old upvalue */
+        }
+    }
+};
+
+const singlevar = function(ls, vr) {
+    let varname = str_checkname(ls);
+    let fs = ls.fs;
+    singlevaraux(fs, varname, vr, 1);
+    if (vr.k === expkind.VVOID) {  /* global name? */
+        let key = new expdesc();
+        singlevaraux(fs, ls.envn, vr, 1);  /* get environment variable */
+        assert(vr.k !== expkind.VVOID);  /* this one must exist */
+        codestring(ls, key, varname);  /* key is variable name */
+        lcode.luaK_indexed(fs, vr, key);  /* env[varname] */
+    }
+};
+
+const adjust_assign = function(ls, nvars, nexps, e) {
+    let fs = ls.fs;
+    let extra = nvars - nexps;
+    if (hasmultret(e.k)) {
+        extra++;  /* includes call itself */
+        if (extra < 0) extra = 0;
+        lcode.luaK_setreturns(fs, e, extra);  /* last exp. provides the difference */
+        if (extra > 1) lcode.luaK_reserveregs(fs, extra - 1);
+    } else {
+        if (e.k !== expkind.VVOID) lcode.luaK_exp2nextreg(fs, e);  /* close last expression */
+        if (extra > 0) {
+            let reg = fs.freereg;
+            lcode.luaK_reserveregs(fs, extra);
+            lcode.luaK_nil(fs, reg, extra);
+        }
+    }
+    if (nexps > nvars)
+        ls.fs.freereg -= nexps - nvars;  /* remove extra values */
+};
+
+const enterlevel = function(ls) {
+    let L = ls.L;
+    ++L.nCcalls;
+    checklimit(ls.fs, L.nCcalls, llimit.LUAI_MAXCCALLS, "JS levels");
+};
+
+const leavelevel = function(ls) {
+    return ls.L.nCcalls--;
+};
+
+const closegoto = function(ls, g, label) {
+    let fs = ls.fs;
+    let gl = ls.dyd.gt;
+    let gt = gl.arr[g];
+    assert(gt.name.value === label.name.value);
+    if (gt.nactvar < label.nactvar) {
+        let vname = getlocvar(fs, gt.nactvar).varname;
+        semerror(ls, `<goto ${gt.name.value}> at line ${gt.line} jumps into the scope of local '${vname.value}'`);
+    }
+    lcode.luaK_patchlist(fs, gt.pc, label.pc);
+    /* remove goto from pending list */
+    for (let i = g; i < gl.n - 1; i++)
+        gl.arr[i] = gl.arr[i + 1];
+    gl.n--;
+};
+
+/*
+** try to close a goto with existing labels; this solves backward jumps
+*/
+const findlabel = function(ls, g) {
+    let bl = ls.fs.bl;
+    let dyd = ls.dyd;
+    let gt = dyd.gt.arr[g];
+    /* check labels in current block for a match */
+    for (let i = bl.firstlabel; i < dyd.label.n; i++) {
+        let lb = dyd.label.arr[i];
+        if (lb.name.value === gt.name.value) {  /* correct label? */
+            if (gt.nactvar > lb.nactvar && (bl.upval || dyd.label.n > bl.firstlabel))
+                lcode.luaK_patchclose(ls.fs, gt.pc, lb.nactvar);
+            closegoto(ls, g, lb);  /* close it */
+            return true;
+        }
+    }
+    return false;  /* label not found; cannot close goto */
+};
+
+const newlabelentry = function(ls, l, name, line, pc) {
+    let n = l.n;
+    l.arr[n] = new Labeldesc();
+    l.arr[n].name = name;
+    l.arr[n].line = line;
+    l.arr[n].nactvar = ls.fs.nactvar;
+    l.arr[n].pc = pc;
+    l.n = n + 1;
+    return n;
+};
+
+/*
+** check whether new label 'lb' matches any pending gotos in current
+** block; solves forward jumps
+*/
+const findgotos = function(ls, lb) {
+    let gl = ls.dyd.gt;
+    let i = ls.fs.bl.firstgoto;
+    while (i < gl.n) {
+        if (gl.arr[i].name.value === lb.name.value)
+            closegoto(ls, i, lb);
+        else
+            i++;
+    }
+};
+
+/*
+** export pending gotos to outer level, to check them against
+** outer labels; if the block being exited has upvalues, and
+** the goto exits the scope of any variable (which can be the
+** upvalue), close those variables being exited.
+*/
+const movegotosout = function(fs, bl) {
+    let i = bl.firstgoto;
+    let gl = fs.ls.dydy.gt;
+    /* correct pending gotos to current block and try to close it
+       with visible labels */
+    while (i < gl.n) {
+        let gt = gl.arr[i];
+        if (gt.nactvar > bl.nactvar) {
+            if (bl.upval)
+                lcode.luaK_patchclose(fs, gt.pc, bl.nactvar);
+            gt.nactvar = bl.nactvar;
+        }
+        if (!findlabel(fs.ls, i))
+            i++;  /* move to next one */
+    }
+};
+
+const enterblock = function(fs, bl, isloop) {
+    bl.isloop = isloop;
+    bl.nactvar = fs.nactvar;
+    bl.firstlabel = fs.ls.dyd.label.n;
+    bl.firstgoto = fs.ls.dyd.gt.n;
+    bl.upval = 0;
+    bl.previous = fs.bl;
+    fs.bl = bl;
+    assert(fs.freereg === fs.nactvar);
+};
+
+/*
+** create a label named 'break' to resolve break statements
+*/
+const breaklabel = function(ls) {
+    let n = new TValue(lua.CT.LUA_TLNGSTR, "break");
+    let l = newlabelentry(ls, ls.dyd.label, n, 0, ls.fs.pc);
+    findgotos(ls, ls.dyd.label.arr[l]);
+};
+
+/*
+** generates an error for an undefined 'goto'; choose appropriate
+** message when label name is a reserved word (which can only be 'break')
+*/
+const undefgoto = function(ls, gt) {
+    const msg = llex.isreserved(gt.name.value)
+                ? `<${gt.name.value}> at line ${gt.line} not inside a loop`
+                : `no visible label '${gt.name.value}' for <goto> at line ${gt.line}`;
+    semerror(ls, msg);
+};
+
+/*
+** adds a new prototype into list of prototypes
+*/
+const addprototype = function(ls) {
+    let clp = new Proto();
+    let L = ls.L;
+    let fs = ls.fs;
+    let f = fs.f;  /* prototype of current function */
+    f.p[fs.np++] = clp;
+    return clp;
+};
+
+/*
+** codes instruction to create new closure in parent function.
+*/
+const codeclosure = function(ls, v) {
+    let fs = ls.fs.prev;
+    init_exp(v, expkind.VRELOCABLE, lcode.luaK_codeABx(fs, OpCodesI.OP_CLOSURE, 0, fs.np -1));
+    lcode.luaK_exp2nextreg(fs, v);  /* fix it at the last register */
+};
+
+const open_func = function(ls, fs, bl) {
+    fs.prev = ls.fs;  /* linked list of funcstates */
+    fs.ls = ls;
+    ls.fs = fs;
+    fs.pc = 0;
+    fs.lasttarget = 0;
+    fs.jpc = lcode.NO_JUMP;
+    fs.freereg = 0;
+    fs.nk = 0;
+    fs.np = 0;
+    fs.nups = 0;
+    fs.nlocvars = 0;
+    fs.nactvar = 0;
+    fs.firstlocal = ls.dyd.actvar.n;
+    fs.bl = null;
+    let f = new Proto();
+    f = fs.f;
+    f.source = ls.source;
+    f.maxstacksize = 2;  /* registers 0/1 are always valid */
+    enterblock(fs, bl, false);
+};
+
+const leaveblock = function(fs) {
+    let bl = fs.bl;
+    let ls = fs.ls;
+    if (bl.previous && bl.upval) {
+        /* create a 'jump to here' to close upvalues */
+        let j = lcode.luaK_jump(fs);
+        lcode.luaK_patchclose(fs, j , bl.nactvar);
+        lcode.luaK_patchtohere(fs, j);
+    }
+
+    if (bl.isloop)
+        breaklabel(ls);  /* close pending breaks */
+
+    fs.bl = bl.previous;
+    removevars(fs, bl.nactvar);
+    assert(bl.nactvar === fs.nactvar);
+    fs.freereg = fs.nactvar;  /* free registers */
+    ls.dyd.label.n = bl.firstlabel;  /* remove local labels */
+    if (bl.previous)  /* inner block? */
+        movegotosout(fs, bl);  /* update pending gotos to outer block */
+    else if (bl.firstgoto < ls.dyd.gt.n)  /* pending gotos in outer block? */
+        undefgoto(ls, ls.dyd.gt.arr[bl.firstgoto]);  /* error */
+};
+
+const close_func = function(ls) {
+    let L = ls.L;
+    let fs = ls.fs;
+    let f = fs.f;
+    lcode.luaK_ret(fs, 0, 0);  /* final return */
+    leaveblock(fs);
+    ls.fs = fs.prev;
+};
+
+/*============================================================*/
+/* GRAMMAR RULES */
+/*============================================================*/
+
+const block_follow = function(ls, withuntil) {
+    switch (ls.t.token) {
+        case R.TK_ELSE: case R.TK_ELSEIF:
+        case R.TK_END: case R.TK_EOS:
+            return true;
+        case R.TK_UNTIL: return withuntil;
+        default: return false;
+    }
+};
+
+const statlist = function(ls) {
+    /* statlist -> { stat [';'] } */
+    while (!block_follow(ls, 1)) {
+        if (ls.t.token === R.TK_RETURN) {
+            statement(ls);
+            return;  /* 'return' must be last statement */
+        }
+        statement(ls);
+    }
+};
+
+const fieldsel = function(ls, v) {
+    /* fieldsel -> ['.' | ':'] NAME */
+    let fs = ls.fs;
+    let key = new expdesc();
+    lcode.luaK_exp2anyregup(fs, v);
+    llex.luaX_next(ls);  /* skip the dot or colon */
+    checkname(ls, key);
+    lcode.luaK_indexed(fs, v, key);
+};
+
+const yindex = function(ls, v) {
+    /* index -> '[' expr ']' */
+    llex.luaX_next(ls);  /* skip the '[' */
+    expr(ls, v);
+    lcode.luaK_exp2val(ls.fs, v);
+    checknext(ls, ']');
+};
+
+/*
+** {======================================================================
+** Rules for Constructors
+** =======================================================================
+*/
+
+class ConsControl {
+    constructor() {
+        this.v = new expdesc(); /* last list item read */
+        this.t = new expdesc(); /* table descriptor */
+        this.nh = NaN;          /* total number of 'record' elements */
+        this.na = NaN;          /* total number of array elements */
+        this.tostore = NaN;     /* number of array elements pending to be stored */
+    }
+}
+
+const recfield = function(ls, cc) {
+    /* recfield -> (NAME | '['exp1']') = exp1 */
+    let fs = ls.fs;
+    let reg = ls.fs.freereg;
+    let key = new expdesc();
+    let val = new expdesc();
+
+    if (ls.t.token === R.TK_NAME) {
+        checklimit(fs, cc.nh, Number.MAX_SAFE_INTEGER, "items in a constructor");
+        checkname(ls, key);
+    } else  /* ls->t.token === '[' */
+        yindex(ls, key);
+    cc.nh++;
+    checknext(ls, '=');
+    let rkkey = lcode.luaK_exp2RK(fs, key);
+    expr(ls, val);
+    lcode.luaK_codeABC(fs, OpCodesI.OP_SETTABLE, cc.t.u.info, rkkey, lcode.luaK_exp2RK(fs, val));
+    fs.freereg = reg;  /* free registers */
+};
+
+const closelistfield = function(fs, cc) {
+    if (cc.v.k === expkind.VVOID) return;  /* there is no list item */
+    lcode.luaK_exp2nextreg(fs, cc.v);
+    cc.v.k = expkind.VVOID;
+    if (cc.tostore === lopcode.LFIELDS_PER_FLUSH) {
+        lcode.luaK_setlist(fs, cc.t.u.info, cc.na, cc.tostore);  /* flush */
+        cc.tostore = 0;  /* no more items pending */
+    }
+};
+
+const lastlistfield = function(fs, cc) {
+    if (cc.tostore === 0) return;
+    if (hasmultret(cc.v.k)) {
+        lcode.luaK_setmultret(fs, cc.v);
+        lcode.luaK_setlist(fs, cc.t.u.info, cc.na, lua.LUA_MULTRET);
+        cc.na--;  /* do not count last expression (unknown number of elements) */
+    } else {
+        if (cc.v.k !== expkind.VVOID)
+            lcode.luaK_exp2nextreg(fs, cc.v);
+        lcode.luaK_setlist(fs, cc.t.u.info, cc.na, cc.tostore);
+    }
+};
+
+const listfield = function(ls, cc) {
+    /* listfield -> exp */
+    expr(ls, cc.v);
+    checklimit(ls.fs, cc.na, Number.MAX_SAFE_INTEGER, "items in a constructor");
+    cc.na++;
+    cc.tostore++;
+};
+
+const field = function(ls, cc) {
+    /* field -> listfield | recfield */
+    switch (ls.t.token) {
+        case R.TK_NAME: {  /* may be 'listfield' or 'recfield' */
+            if (llex.luaX_lookahead(ls) !== '=')  /* expression? */
+                listfield(ls, cc);
+            else
+                recfield(ls, cc);
+            break;
+        }
+        case '[': {
+            recfield(ls, cc);
+            break;
+        }
+        default: {
+            listfield(ls, cc);
+            break;
+        }
+    }
+};
+
+const constructor = function(ls, t) {
+    /* constructor -> '{' [ field { sep field } [sep] ] '}'
+       sep -> ',' | ';' */
+    let fs = ls.fs;
+    let line = ls.linenumber;
+    let pc = lcode.luaK_codeABC(fs, OpCodesI.OP_NEWTABLE, 0, 0, 0);
+    let cc = new ConsControl();
+    cc.na = cc.nh = cc.tostore = 0;
+    cc.t = t;
+    init_exp(t, expkind.VRELOCABLE, pc);
+    init_exp(cc.v, expkind.VVOID, 0);  /* no value (yet) */
+    lcode.luaK_exp2nextreg(ls.fs, t);  /* fix it at stack top */
+    checknext(ls, '{');
+    do {
+        assert(cc.v.k === expkind.VVOID || cc.tostore > 0);
+        if (ls.t.token === '}') break;
+        closelistfield(fs, cc);
+        field(ls, cc);
+    } while (testnext(ls, ',') || testnext(ls, ';'));
+    check_match(ls, '}', '{', line);
+    lastlistfield(fs, cc);
+    lopcode.SETARG_B(fs.f.code[pc], lobject.luaO_int2fb(cc.na));  /* set initial array size */
+    lopcode.SETARG_C(fs.f.code[pc], lobject.luaO_int2fb(cc.nh));  /* set initial table size */
+};
+
+/* }====================================================================== */
+
+const parlist = function(ls) {
+    /* parlist -> [ param { ',' param } ] */
+    let fs = ls.fs;
+    let f = fs.f;
+    let nparams = 0;
+    f.is_vararg = 0;
+    if (ls.t.token !== ')') {  /* is 'parlist' not empty? */
+        do {
+            switch (ls.t.token) {
+                case R.TK_NAME: {  /* param -> NAME */
+                    new_localvar(ls, str_checkname(ls));
+                    nparams++;
+                    break;
+                }
+                case R.TK_DOTS: {  /* param -> '...' */
+                    llex.luaX_next(ls);
+                    f.is_vararg = 1;  /* declared vararg */
+                    break;
+                }
+                default: llex.luaX_syntaxerror(ls, "<name> or '...' expected");
+            }
+        } while(!f.is_vararg && testnext(ls, ','));
+    }
+    adjustlocalvars(ls, nparams);
+    f.numparams = fs.nactvar;
+    lcode.luaK_reserveregs(fs, fs.nactvar);  /* reserve register for parameters */
+};
+
+const body = function(ls, e, ismethod, line) {
+    /* body ->  '(' parlist ')' block END */
+    let new_fs = new FuncState();
+    let bl = new BlockCnt();
+    new_fs.f = addprototype(ls);
+    new_fs.f.linedefined = line;
+    open_func(ls, new_fs, bl);
+    checknext(ls, '(');
+    if (ismethod) {
+        new_localvarliteral(ls, "self");  /* create 'self' parameter */
+        adjustlocalvars(ls, 1);
+    }
+    parlist(ls);
+    checknext(ls, ')');
+    statlist(ls);
+    new_fs.f.lastlinedefined = ls.linenumber;
+    check_match(ls, R.TK_END, R.TK_FUNCTION, line);
+    codeclosure(ls, e);
+    close_func(ls);
+};
+
+const explist = function(ls, v) {
+    /* explist -> expr { ',' expr } */
+    let n = 1;  /* at least one expression */
+    expr(ls, v);
+    while (testnext(ls, ',')) {
+        lcode.luaK_exp2nextreg(ls.fs, v);
+        expr(ls, v);
+        n++;
+    }
+    return n;
+};
+
+const funcargs = function(ls, f, line) {
+    let fs = ls.fs;
+    let args = new expdesc();
+    switch (ls.t.token) {
+        case '(': {  /* funcargs -> '(' [ explist ] ')' */
+            llex.luaX_next(ls);
+            if (ls.t.token === ')')  /* arg list is empty? */
+                args.k = expkind.VVOID;
+            else {
+                explist(ls, args);
+                lcode.luaK_setmultret(fs, args);
+            }
+            check_match(ls, ')', '(', line);
+            break;
+        }
+        case '{': {  /* funcargs -> constructor */
+            constructor(ls, args);
+            break;
+        }
+        case R.TK_STRING: {  /* funcargs -> STRING */
+            codestring(ls, args, ls.t.seminfo.ts);
+            llex.luaX_next(ls);  /* must use 'seminfo' before 'next' */
+            break;
+        }
+        default: {
+            llex.luaX_syntaxerror(ls, "function arguments expected");
+        }
+    }
+    assert(f.k === expkind.VNONRELOC);
+    let nparams;
+    let base = f.u.info;  /* base register for call */
+    if (hasmultret(args.k))
+        nparams = lua.LUA_MULTRET;  /* open call */
+    else {
+        if (args.k !== expkind.VVOID)
+            lcode.luaK_exp2nextreg(fs, args);  /* close last argument */
+        nparams = fs.freereg - (base+1);
+    }
+    init_exp(f, expkind.VCALL, lcode.luaK_codeABC(fs, OpCodesI.OP_CALL, base, nparams+1, 2));
+    lcode.luaK_fixline(fs, line);
+    fs.freereg = base + 1; /* call remove function and arguments and leaves (unless changed) one result */
+};
+
+/*
+** {======================================================================
+** Expression parsing
+** =======================================================================
+*/
+
+const primaryexp = function(ls, v) {
+    /* primaryexp -> NAME | '(' expr ')' */
+    switch (ls.t.token) {
+        case '(': {
+            let line = ls.linenumber;
+            llex.luaX_next(ls);
+            expr(ls, v);
+            check_match(ls, ')', '(', line);
+            lcode.luaK_dischargevars(ls.fs, v);
+            return;
+        }
+        case R.TK_NAME: {
+            singlevar(ls, v);
+            return;
+        }
+        default: {
+            llex.luaX_syntaxerror(ls, "unexpected symbol");
+        }
+    }
+};
+
+const suffixedexp = function(ls, v) {
+    /* suffixedexp ->
+       primaryexp { '.' NAME | '[' exp ']' | ':' NAME funcargs | funcargs } */
+    let fs = ls.fs;
+    let line = ls.linenumber;
+    primaryexp(ls, v);
+    for (;;) {
+        switch (ls.t.token) {
+            case '.': {  /* fieldsel */
+                fieldsel(ls, v);
+                break;
+            }
+            case '[': {  /* '[' exp1 ']' */
+                let key = new expdesc();
+                lcode.luaK_exp2anyregup(fs, v);
+                yindex(ls, key);
+                lcode.luaK_indexed(fs, v, key);
+                break;
+            }
+            case ':': {  /* ':' NAME funcargs */
+                let key = new expdesc();
+                llex.luaX_next(ls);
+                checkname(ls, key);
+                lcode.luaK_self(fs, v, key);
+                funcargs(ls, v, line);
+                break;
+            }
+            case '(': case R.TK_STRING: case '{': {  /* funcargs */
+                lcode.luaK_exp2nextreg(fs, v);
+                funcargs(ls, v, line);
+                break;
+            }
+            default: return;
+        }
+    }
+};
+
+const simpleexp = function(ls, v) {
+    /* simpleexp -> FLT | INT | STRING | NIL | TRUE | FALSE | ... |
+       constructor | FUNCTION body | suffixedexp */
+    switch (ls.t.token) {
+        case R.TK_FLT: {
+            init_exp(v, expkind.VFLT, 0);
+            v.u.nval = ls.t.seminfo.r;
+            break;
+        }
+        case R.TK_INT: {
+            init_exp(v, expkind.VKINT, 0);
+            v.u.ival = ls.t.seminfo.i;
+            break;
+        }
+        case R.TK_STRING: {
+            codestring(ls, v, ls.t.seminfo.ts);
+            break;
+        }
+        case R.TK_NIL: {
+            init_exp(v, expkind.VNIL, 0);
+            break;
+        }
+        case R.TK_TRUE: {
+            init_exp(v, expkind.VTRUE, 0);
+            break;
+        }
+        case R.TK_FALSE: {
+            init_exp(v, expkind.VFALSE, 0);
+            break;
+        }
+        case R.TK_DOTS: {  /* vararg */
+            let fs = ls.fs;
+            check_condition(ls, fs.f.is_vararg, "cannot use '...' outside a vararg function");
+            init_exp(v, expkind.VVARARG, lcode.luaK_codeABC(fs, OpCodesI.OP_VARARG, 0, 1, 0));
+            break;
+        }
+        case '{': {  /* constructor */
+            constructor(ls, v);
+            return;
+        }
+        case R.TK_FUNCTION: {
+            llex.luaX_next(ls);
+            body(ls, v, 0, ls.linenumber);
+            return;
+        }
+        default: {
+            suffixedexp(ls, v);
+            return;
+        }
+    }
+    llex.luaX_next(ls);
+};
+
+const getunopr = function(op) {
+    switch (op) {
+        case R.TK_NOT: return UnOpr.OPR_NOT;
+        case '-':      return UnOpr.OPR_MINUS;
+        case '~':      return UnOpr.OPR_BNOT;
+        case '#':      return UnOpr.OPR_LEN;
+        default:       return UnOpr.OPR_NOUNOPR;
+    }
+};
+
+const getbinopr = function(op) {
+    switch (op) {
+        case '+':         return BinOpr.OPR_ADD;
+        case '-':         return BinOpr.OPR_SUB;
+        case '*':         return BinOpr.OPR_MUL;
+        case '%':         return BinOpr.OPR_MOD;
+        case '^':         return BinOpr.OPR_POW;
+        case '/':         return BinOpr.OPR_DIV;
+        case R.TK_IDIV:   return BinOpr.OPR_IDIV;
+        case '&':         return BinOpr.OPR_BAND;
+        case '|':         return BinOpr.OPR_BOR;
+        case '~':         return BinOpr.OPR_BXOR;
+        case R.TK_SHL:    return BinOpr.OPR_SHL;
+        case R.TK_SHR:    return BinOpr.OPR_SHR;
+        case R.TK_CONCAT: return BinOpr.OPR_CONCAT;
+        case R.TK_NE:     return BinOpr.OPR_NE;
+        case R.TK_EQ:     return BinOpr.OPR_EQ;
+        case '<':         return BinOpr.OPR_LT;
+        case R.TK_LE:     return BinOpr.OPR_LE;
+        case '>':         return BinOpr.OPR_GT;
+        case R.TK_GE:     return BinOpr.OPR_GE;
+        case R.TK_AND:    return BinOpr.OPR_AND;
+        case R.TK_OR:     return BinOpr.OPR_OR;
+        default:          return BinOpr.OPR_NOBINOPR;
+    }
+};
+
+const priority = [  /* ORDER OPR */
+    {left: 10, right: 10}, {left: 10, right: 10},     /* '+' '-' */
+    {left: 11, right: 11}, {left: 11, right: 11},     /* '*' '%' */
+    {left: 14, right: 13},               /* '^' (right associative) */
+    {left: 11, right: 11}, {left: 11, right: 11},     /* '/' '//' */
+    {left: 6, right: 6}, {left: 4, right: 4}, {left: 5, right: 5}, /* '&' '|' '~' */
+    {left: 7, right: 7}, {left: 7, right: 7},         /* '<<' '>>' */
+    {left: 9, right: 8},                 /* '..' (right associative) */
+    {left: 3, right: 3}, {left: 3, right: 3}, {left: 3, right: 3}, /* ==, <, <= */
+    {left: 3, right: 3}, {left: 3, right: 3}, {left: 3, right: 3}, /* ~=, >, >= */
+    {left: 2, right: 2}, {left: 1, right: 1}          /* and, or */
+];
+
+const UNARY_PRIORITY = 12;
+
+/*
+** subexpr -> (simpleexp | unop subexpr) { binop subexpr }
+** where 'binop' is any binary operator with a priority higher than 'limit'
+*/
+const subexpr = function(ls, v, limit) {
+    enterlevel(ls);
+    let uop = getunopr(ls.t.token);
+    if (uop !== UnOpr.OPR_NOUNOPR) {
+        let line = ls.linenumber;
+        llex.luaX_next(ls);
+        subexpr(ls, v, UNARY_PRIORITY);
+        lcode.luaK_prefix(ls.fs, uop, v, line);
+    } else
+        simpleexp(ls, v);
+    /* expand while operators have priorities higher than 'limit' */
+    let op = getbinopr(ls.t.token);
+    while (op !== BinOpr.OPR_NOBINOPR && priority[op].left > limit) {
+        let v2 = new expdesc();
+        let line = ls.linenumber;
+        llex.luaX_next(ls);
+        lcode.luaK_infix(ls.fs, op, v);
+        /* read sub-expression with higher priority */
+        let nextop = subexpr(ls, v2, priority[op].right);
+        lcode.luaK_posfix(ls.fs, op, v, v2, line);
+        op = nextop;
+    }
+    leavelevel(ls);
+    return op;  /* return first untreated operator */
+};
+
+const expr = function(ls, v) {
+    subexpr(ls, v, 0);
+};
+
+/* }==================================================================== */
+
+
+
+/*
+** {======================================================================
+** Rules for Statements
+** =======================================================================
+*/
+
+const block = function(ls) {
+    /* block -> statlist */
+    let fs = ls.fs;
+    let bl = new BlockCnt();
+    enterblock(fs, bl, 0);
+    statlist(ls);
+    leaveblock(fs);
+};
+
+/*
+** structure to chain all variables in the left-hand side of an
+** assignment
+*/
+class LHS_assign {
+    constructor() {
+        this.prev = null;
+        this.v = new expdesc();  /* variable (global, local, upvalue, or indexed) */
+    }
+}
+
+/*
+** check whether, in an assignment to an upvalue/local variable, the
+** upvalue/local variable is begin used in a previous assignment to a
+** table. If so, save original upvalue/local value in a safe place and
+** use this safe copy in the previous assignment.
+*/
+const check_conflict = function(ls, lh, v) {
+    let fs = ls.fs;
+    let extra = fs.freereg;  /* eventual position to save local variable */
+    let conflict = false;
+    for (; lh; lh = lh.prev) {  /* check all previous assignments */
+        if (lh.v.k === expkind.VINDEXED) {  /* assigning to a table? */
+            /* table is the upvalue/local being assigned now? */
+            if (lh.v.u.ind.vt === v.k && lh.v.u.ind.t === v.u.info) {
+                conflict = true;
+                lh.v.u.ind.vt = expkind.VLOCAL;
+                lh.v.u.ind.t = extra;  /* previous assignment will use safe copy */
+            }
+            /* index is the local being assigned? (index cannot be upvalue) */
+            if (v.k === expkind.VLOCAL && lh.v.u.ind.idx === v.u.info) {
+                conflict = true;
+                lh.v.u.ind.idx = extra;  /* previous assignment will use safe copy */
+            }
+        }
+    }
+    if (conflict) {
+        /* copy upvalue/local value to a temporary (in position 'extra') */
+        let op = v.k === expkind.VLOCAL ? OpCodesI.OP_MOVE : OpCodesI.OP_GETUPVAL;
+        lcode.luaK_codeABC(fs, op, extra, v.u.info, 0);
+        lcode.luaK_reserveregs(fs, 1);
+    }
+};
+
+const assignment = function(ls, lh, nvars) {
+    let e = new expdesc();
+    check_condition(ls, vkisvar(lh.v.k), "syntax error");
+    if (testnext(ls, ',')) {  /* assignment -> ',' suffixedexp assignment */
+        let nv = new LHS_assign();
+        nv.prev = lh;
+        suffixedexp(ls, nv.v);
+        if (nv.v.k !== expkind.VINDEXED)
+            check_conflict(ls, lh, nv.v);
+        checklimit(ls.fs, nvars + ls.L.nCcalls, llimit.LUAI_MAXCCALLS, "JS levels");
+        assignment(ls, nv, nvars + 1);
+    } else {  /* assignment -> '=' explist */
+        checknext(ls, '=');
+        let nexps = explist(ls, e);
+        if (nexps !== nvars)
+            adjust_assign(ls, nvars, nexps, e);
+        else {
+            lcode.luaK_setoneret(ls.fs, e);  /* close last expression */
+            lcode.luaK_storevar(ls.fs, lh.v, e);
+            return;  /* avoid default */
+        }
+    }
+    init_exp(e, expkind.VNONRELOC, ls.fs.freereg-1);  /* default assignment */
+    lcode.luaK_storevar(ls.fs, lh.v, e);
+};
+
+const cond = function(ls) {
+    /* cond -> exp */
+    let v = expdesc();
+    expr(ls, v);  /* read condition */
+    if (v.k === expkind.VNIL) v.k = expkind.VFALSE;  /* 'falses' are all equal here */
+    lcode.luaK_goiftrue(ls.fs, v);
+    return v;
+};
+
+const gotostat = function(ls, pc) {
+    let line = ls.linenumber;
+    let label;
+    if (testnext(ls, R.TK_GOTO))
+        label = str_checkname(ls);
+    else {
+        llex.luaX_next(ls);  /* skip break */
+        label = new TValue(lua.CT.LUA_TLNGSTR, "break");
+    }
+    let g = newlabelentry(ls, ls.dyd.gt, label, line, pc);
+    findlabel(ls, g);  /* close it if label already defined */
+};
+
+/* check for repeated labels on the same block */
+const checkrepeated = function(fs, ll, label) {
+    for (let i = fs.bl.firstlabel; i < ll.n; i++) {
+        if (label.value === ll.arr[i].name.value) {
+            semerror(fs.ls, `label '${label}' already defined on line ${ll.arr[i].line}`);
+        }
+    }
+};
+
+/* skip no-op statements */
+const skipnoopstat = function(ls) {
+    while (ls.t.token === ';' || ls.t.token === R.TK_DBCOLON)
+        statement(ls);
+};
+
+const labelstat = function(ls, label, line) {
+    /* label -> '::' NAME '::' */
+    let fs = ls.fs;
+    let ll = ls.dyd.label;
+    let l;  /* index of new label being created */
+    checkrepeated(fs, ll, label);  /* check for repeated labels */
+    checknext(ls, R.TK_DBCOLON);  /* skip double colon */
+    /* create new entry for this label */
+    l = newlabelentry(ls, ll, label, line, lcode.luaK_getlabel(fs));
+    skipnoopstat(ls);  /* skip other no-op statements */
+    if (block_follow(ls, 0)) {  /* label is last no-op statement in the block? */
+        /* assume that locals are already out of scope */
+        ll.arr[l].nactvar = fs.bl.nactvar;
+    }
+    findgotos(ls, ll.arr[l]);
+};
+
+const whilestat = function(ls, line) {
+    /* whilestat -> WHILE cond DO block END */
+    let fs = ls.fs;
+    let bl = new BlockCnt();
+    llex.luaX_next(ls);  /* skip WHILE */
+    let whileinit = lcode.luaK_getlabel(fs);
+    let condexit = cond(ls);
+    enterblock(fs, bl, 1);
+    checknext(ls, R.TK_DO);
+    block(ls);
+    lcode.luaK_jumpto(fs, whileinit);
+    check_match(ls, R.TK_END, R.TK_WHILE, line);
+    leaveblock(fs);
+    lcode.luaK_patchtohere(fs, condexit);  /* false conditions finish the loop */
+};
+
+const repeatstat = function(ls, line) {
+    /* repeatstat -> REPEAT block UNTIL cond */
+    let fs = ls.fs;
+    let repeat_init = lcode.luaK_getlabel(fs);
+    let bl1 = new BlockCnt();
+    let bl2 = new BlockCnt();
+    enterblock(fs, bl1, 1);  /* loop block */
+    enterblock(fs, bl2, 0);  /* scope block */
+    llex.luaX_next(ls);  /* skip REPEAT */
+    statlist(ls);
+    check_match(ls, R.TK_UNTIL, R.TK_REPEAT, line);
+    let condexit = cond(ls);  /* read condition (inside scope block) */
+    if (bl2.upval)  /* upvalues? */
+        lcode.luaK_patchclose(fs, condexit, bl2.nactvar);
+    leaveblock(fs);  /* finish scope */
+    lcode.luaK_patchlist(fs, condexit, repeat_init);  /* close the loop */
+    leaveblock(fs);  /* finish loop */
+};
+
+const exp1 = function(ls) {
+    let e = new expdesc();
+    expr(ls, e);
+    lcode.luaK_exp2nextreg(ls.fs, e);
+    assert(e.k === expkind.VNONRELOC);
+    let reg = e.u.info;
+    return reg;
+};
+
+const forbody = function(ls, base, line, nvars, isnum) {
+    /* forbody -> DO block */
+    let bl = new BlockCnt();
+    let fs = ls.fs;
+    let endfor;
+    adjustlocalvars(ls, 3);  /* control variables */
+    checknext(ls, R.TK_DO);
+    let prep = isnum ? lcode.luaK_codeAsBx(fs, OpCodesI.OP_FORPREP, base, lcode.NO_JUMP) : lcode.luaK_jump(fs);
+    enterblock(fs, bl, 0);  /* scope for declared variables */
+    adjustlocalvars(ls, nvars);
+    lcode.luaK_reserveregs(fs, nvars);
+    block(ls);
+    leaveblock(fs);  /* end of scope for declared variables */
+    lcode.luaK_patchtohere(fs, prep);
+    if (isnum)  /* end of scope for declared variables */
+        endfor = lcode.luaK_codeAsBx(fs, OpCodesI.OP_FORLOOP, base, lcode.NO_JUMP);
+    else {  /* generic for */
+        lcode.luaK_codeABC(fs, OpCodesI.OP_TFORLOOP, base + 2, lcode.NO_JUMP);
+        lcode.luaK_fixline(fs, line);
+        endfor = lcode.luaK_codeAsBx(fs, OpCodesI.OP_TFORLOOP, base + 2, lcode.NO_JUMP);
+    }
+    lcode.luaK_patchlist(fs, endfor, prep + 1);
+    lcode.luaK_fixline(fs, line);
+};
+
+const fornum = function(ls, varname, line) {
+    /* fornum -> NAME = exp1,exp1[,exp1] forbody */
+    let fs = ls.fs;
+    let base = fs.freereg;
+    new_localvarliteral(ls, "(for index)");
+    new_localvarliteral(ls, "(for limit)");
+    new_localvarliteral(ls, "(for step)");
+    new_localvar(ls, varname);
+    checknext(ls, '=');
+    exp1(ls);  /* initial value */
+    checknext(ls, ',');
+    exp1(ls);  /* limit */
+    if (testnext(ls, ','))
+        exp1(ls);  /* optional step */
+    else {  /* default step = 1 */
+        lcode.luaK_codek(fs, fs.freereg, lcode.luaK_intK(fs, 1));
+        lcode.luaK_reserveregs(fs, 1);
+    }
+    forbody(ls, base, line, 1, 1);
+};
+
+const forlist = function(ls, indexname) {
+    /* forlist -> NAME {,NAME} IN explist forbody */
+    let fs = ls.fs;
+    let e = new expdesc();
+    let nvars = 4;  /* gen, state, control, plus at least one declared var */
+    let base = fs.freereg();
+    /* create control variables */
+    new_localvarliteral(ls, "(for generator)");
+    new_localvarliteral(ls, "(for state)");
+    new_localvarliteral(ls, "(for control)");
+    /* create declared variables */
+    new_localvar(ls, indexname);
+    while (testnext(ls, ',')) {
+        new_localvar(ls, str_checkname(ls));
+        nvars++;
+    }
+    checknext(ls, R.TK_IN);
+    let line = ls.linenumber;
+    adjust_assign(ls, 3, explist(ls, e), e);
+    lcode.luaK_checkstack(fs, 3);  /* extra space to call generator */
+    forbody(ls, base, line, nvars - 3, 0);
+};
+
+const forstat = function(ls, line) {
+    /* forstat -> FOR (fornum | forlist) END */
+    let fs = ls.fs;
+    let bl = new BlockCnt();
+    enterblock(fs, bl, 1);  /* scope for loop and control variables */
+    llex.luaX_next(ls);  /* skip 'for' */
+    let varname = str_checkname(ls);  /* first variable name */
+    switch (ls.t.token) {
+        case '=': fornum(ls, varname, line); break;
+        case ',': case R.TK_IN: forlist(ls, varname); break;
+        default: llex.luaX_syntaxerror(ls, "'=' or 'in' expected");
+    }
+    check_match(ls, R.TK_END, R.TK_FOR, line);
+    leaveblock(fs);  /* loop scope ('break' jumps to this point) */
+};
+
+const test_then_block = function(ls, escapelist) {
+    /* test_then_block -> [IF | ELSEIF] cond THEN block */
+    let bl = new BlockCnt();
+    let fs = ls.fs;
+    let v = new expdesc();
+    let jf;  /* instruction to skip 'then' code (if condition is false) */
+
+    llex.luaX_next(ls);  /* skip IF or ELSEIF */
+    expr(ls, v);  /* read condition */
+    checknext(ls, R.TK_THEN);
+
+    if (ls.t.token === R.TK_GOTO || ls.t.token === R.TK_BREAK) {
+        lcode.luaK_goiffalse(ls.fs, v);  /* will jump to label if condition is true */
+        enterblock(fs, bl, false);  /* must enter block before 'goto' */
+        gotostat(ls, v.t);   /* handle goto/break */
+        skipnoopstat(ls);  /* skip other no-op statements */
+        if (block_follow(ls, 0)) {  /* 'goto' is the entire block? */
+            leaveblock(fs);
+            return;  /* and that is it */
+        } else  /* must skip over 'then' part if condition is false */
+            jf = lcode.luaK_jump(fs);
+    } else {  /* regular case (not goto/break) */
+        lcode.luaK_goiftrue(ls.fs, v);  /* skip over block if condition is false */
+        enterblock(fs, bl, false);
+        jf = v.f;
+    }
+
+    statlist(ls);  /* 'then' part */
+    leaveblock(fs);
+    if (ls.t.token === R.TK_ELSE || ls.t.token === R.TK_ELSEIF)  /* followed by 'else'/'elseif'? */
+        escapelist = lcode.luaK_concat(fs, escapelist, lcode.luaK_jump(fs));  /* must jump over it */
+    lcode.luaK_patchtohere(fs, jf);
+};
+
+const ifstat = function(ls, line) {
+    /* ifstat -> IF cond THEN block {ELSEIF cond THEN block} [ELSE block] END */
+    let fs = ls.fs;
+    let escapelist = lcode.NO_JUMP;  /* exit list for finished parts */
+    test_then_block(ls, escapelist);  /* IF cond THEN block */
+    while (ls.t.token === R.TK_ELSEIF)
+        test_then_block(ls, escapelist);  /* ELSEIF cond THEN block */
+    if (testnext(ls, R.TK_ELSE))
+        block(ls);  /* 'else' part */
+    check_match(ls, R.TK_END, R.TK_IF, line);
+    lcode.luaK_patchtohere(fs, escapelist);  /* patch escape list to 'if' end */
+};
+
+const localfunc = function(ls) {
+    let b = new expdesc();
+    let fs = ls.fs;
+    new_localvar(ls, str_checkname(ls));  /* new local variable */
+    adjustlocalvars(ls, 1);  /* enter its scope */
+    body(ls, b, 0, ls.linenumber);  /* function created in next register */
+    /* debug information will only see the variable after this point! */
+    getlocvar(fs, b.u.info).startpc = fs.pc;
+};
+
+const localstat = function(ls) {
+    /* stat -> LOCAL NAME {',' NAME} ['=' explist] */
+    let nvars = 0;
+    let nexps;
+    let e = new expdesc();
+    do {
+        new_localvar(ls, str_checkname(ls));
+        nvars++;
+    } while (testnext(ls, ','));
+    if (testnext(ls, '='))
+        nexps = explist(ls, e);
+    else {
+        e.k = expkind.VVOID;
+        nexps = 0;
+    }
+    adjust_assign(ls, nvars, nexps, e);
+    adjustlocalvars(ls, nvars);
+};
+
+const funcname = function(ls, v) {
+    /* funcname -> NAME {fieldsel} [':' NAME] */
+    let ismethod = 0;
+    singlevar(ls, v);
+    while (ls.t.token === '.')
+        fieldsel(ls, v);
+    if (ls.t.token === ':') {
+        ismethod = 1;
+        fieldsel(ls, v);
+    }
+    return ismethod;
+};
+
+const funcstat = function(ls, line) {
+    /* funcstat -> FUNCTION funcname body */
+    let v = new expdesc();
+    let b = new expdesc();
+    llex.luaX_next(ls);  /* skip FUNCTION */
+    let ismethod = funcname(ls, v);
+    body(ls, b, ismethod, line);
+    lcode.luaK_storevar(ls.fs, v, b);
+    lcode.luaK_fixline(ls.fs, line);  /* definition "happens" in the first line */
+};
+
+const exprstat= function(ls) {
+    /* stat -> func | assignment */
+    let fs = ls.fs;
+    let v = new LHS_assign();
+    suffixedexp(ls, v.v);
+    if (ls.t.token === '=' || ls.t.token === ',') { /* stat . assignment ? */
+        v.prev = null;
+        assignment(ls, v, 1);
+    }
+    else {  /* stat -> func */
+        check_condition(ls, v.v.k === expkind.VCALL, "syntax error");
+        lopcode.SETARG_C(lcode.getinstruction(fs, v.v), 1);  /* call statement uses no results */
+    }
+};
+
+const retstat = function(ls) {
+    /* stat -> RETURN [explist] [';'] */
+    let fs = ls.fs;
+    let e = new expdesc();
+    let first, nret;  /* registers with returned values */
+    if (block_follow(ls, 1) || ls.t.token === ';')
+        first = nret = 0;  /* return no values */
+    else {
+        nret = explist(ls, e);  /* optional return values */
+        if (hasmultret(e.k)) {
+            lcode.luaK_setmultret(fs, e);
+            if (e.k === expkind.VCALL && nret === 1) {  /* tail call? */
+                lopcode.SET_OPCODE(lcode.getinstruction(fs, e), OpCodesI.OP_TAILCALL);
+                assert(lcode.getinstruction(fs, e).A === fs.nactvar);
+            }
+            first = fs.nactvar;
+            nret = lua.LUA_MULTRET;  /* return all values */
+        } else {
+            if (nret === 1)  /* only one single value? */
+                first = lcode.luaK_exp2anyreg(fs, e);
+            else {
+                lcode.luaK_exp2nextreg(fs, e);  /* values must go to the stack */
+                first = fs.nactvar;  /* return all active values */
+                assert(nret === fs.freereg - first);
+            }
+        }
+    }
+    lcode.luaK_ret(fs, first, nret);
+    testnext(ls, ';');  /* skip optional semicolon */
+};
+
+const statement = function(ls) {
+    let line = ls.linenumber;  /* may be needed for error messages */
+    enterlevel(ls);
+    switch(ls.t.token) {
+        case ';': {  /* stat -> ';' (empty statement) */
+            llex.luaX_next(ls);  /* skip ';' */
+            break;
+        }
+        case R.TK_IF: {  /* stat -> ifstat */
+            ifstat(ls, line);
+            break;
+        }
+        case R.TK_WHILE: {  /* stat -> whilestat */
+            whilestat(ls, line);
+            break;
+        }
+        case R.TK_DO: {  /* stat -> DO block END */
+            llex.luaX_next(ls);  /* skip DO */
+            block(ls);
+            check_match(ls, R.TK_END, R.TK_DO, line);
+            break;
+        }
+        case R.TK_FOR: {  /* stat -> forstat */
+            forstat(ls, line);
+            break;
+        }
+        case R.TK_REPEAT: {  /* stat -> repeatstat */
+            repeatstat(ls, line);
+            break;
+        }
+        case R.TK_FUNCTION: {  /* stat -> funcstat */
+            funcstat(ls, line);
+            break;
+        }
+        case R.TK_LOCAL: {  /* stat -> localstat */
+            llex.luaX_next(ls);  /* skip LOCAL */
+            if (testnext(ls, R.TK_FUNCTION))  /* local function? */
+                localfunc(ls);
+            else
+                localstat(ls);
+            break;
+        }
+        case R.TK_DBCOLON: {  /* stat -> label */
+            llex.luaX_next(ls);  /* skip double colon */
+            labelstat(ls, str_checkname(ls), line);
+            break;
+        }
+        case R.TK_RETURN: {  /* skip double colon */
+            llex.luaX_next(ls);  /* skip RETURN */
+            retstat(ls);
+            break;
+        }
+        case R.TK_BREAK:   /* stat -> breakstat */
+        case R.TK_GOTO: {  /* stat -> 'goto' NAME */
+            gotostat(ls, lcode.luaK_jump(ls.fs));
+            break;
+        }
+        default: {  /* stat -> func | assignment */
+            exprstat(ls);
+            break;
+        }
+    }
+
+    assert(ls.fs.f.maxstacksize >= ls.fs.freereg && ls.fs.freereg >= ls.fs.nactvar);
+    ls.fs.freereg = ls.fs.nactvar;  /* free registers */
+    leavelevel(ls);
+};
+
+/*
+** compiles the main function, which is a regular vararg function with an
+** upvalue named LUA_ENV
+*/
+const mainfunc = function(ls, fs) {
+    let bl = new BlockCnt();
+    let v = new expdesc();
+    open_func(ls, fs, bl);
+    fs.f.is_vararg = true;  /* main function is always declared vararg */
+    init_exp(v, expkind.VLOCAL, 0);  /* create and... */
+    newupvalue(fs, ls.envn, v);  /* ...set environment upvalue */
+    llex.luaX_next(ls);  /* read first token */
+    statlist(ls);  /* parse main body */
+    check(ls, R.TK_EOS);
+    close_func(ls);
+};
+
+const luaY_parser = function(L, z, buff, dyd, name, firstchar) {
+    let lexstate = new llex.LexState();
+    let funcstate = new FuncState();
+    let cl = lfunc.luaF_newLclosure(L, 1);  /* create main closure */
+    L.stack[L.top++] = cl;
+    lexstate.h = new Table();  /* create table for scanner */
+    L.stack[L.top++] = lexstate.h;
+    funcstate.f = cl.p = new Proto(L);
+    funcstate.f.source = new TValue(lua.CT.LUA_TLNGSTR, name);
+    lexstate.buff = buff;
+    lexstate.dyd = dyd;
+    dyd.actvar.n = dyd.gt.n = dyd.label.n = 0;
+    llex.luaX_setinput(L, lexstate, z, funcstate.f.source, firstchar);
+    mainfunc(lexstate, funcstate);
+    assert(!funcstate.prev && funcstate.nups === 1 && !lexstate.fs);
+    /* all scopes should be correctly finished */
+    assert(dyd.actvar.n === 0 && dyd.gt.n === 0 && dyd.label.n === 0);
+    L.top--;  /* remove scanner's table */
+    return cl;  /* closure is on the stack, too */
+};
+
+
+module.exports.Dyndata     = Dyndata;
+module.exports.expkind     = expkind;
+module.exports.luaY_parser = luaY_parser;
+module.exports.vkisinreg   = vkisinreg;
\ No newline at end of file
diff --git a/src/lstate.js b/src/lstate.js
index 9a9c9e0..1fc7765 100644
--- a/src/lstate.js
+++ b/src/lstate.js
@@ -105,7 +105,7 @@ const init_registry = function(L, g) {
 
 /*
 ** open parts of the state that may cause memory-allocation errors.
-** ('g->version' != NULL flags that the state was completely build)
+** ('g->version' !== NULL flags that the state was completely build)
 */
 const f_luaopen = function(L) {
     let g = L.l_G;
diff --git a/src/ltablib.js b/src/ltablib.js
index fa43523..a7963d3 100644
--- a/src/ltablib.js
+++ b/src/ltablib.js
@@ -1,4 +1,3 @@
-/* jshint esversion: 6 */
 "use strict";
 
 const assert  = require('assert');
diff --git a/src/lua.js b/src/lua.js
index c7d1fd7..ef5385c 100644
--- a/src/lua.js
+++ b/src/lua.js
@@ -5,6 +5,9 @@ const assert  = require('assert');
 const lualib  = require('./lualib.js');
 const luaconf = require('./luaconf.js');
 
+/* mark for precompiled code ('<esc>Lua') */
+const LUA_SIGNATURE           = "\x1bLua";
+
 const LUA_VERSION_MAJOR       = "5";
 const LUA_VERSION_MINOR       = "3";
 const LUA_VERSION_NUM         = 503;
@@ -25,8 +28,10 @@ const FENGARI_RELEASE         = FENGARI_VERSION + "." + FENGARI_VERSION_RELEASE;
 const FENGARI_COPYRIGHT       = FENGARI_RELEASE + "  Copyright (C) 2017 Benoît Giannangeli\nBased on: " + LUA_COPYRIGHT;
 const FENGARI_AUTHORS         = "B. Giannangeli";
 
+const LUA_VERSUFFIX           = "_" + LUA_VERSION_MAJOR + "_" + LUA_VERSION_MINOR;
+
 const LUA_INIT_VAR            = "LUA_INIT";
-const LUA_INITVARVERSION      = LUA_INIT_VAR + lualib.LUA_VERSUFFIX;
+const LUA_INITVARVERSION      = LUA_INIT_VAR + LUA_VERSUFFIX;
 
 const thread_status = {
     LUA_OK:        0,
@@ -52,6 +57,8 @@ const constant_types = {
     LUA_NUMTAGS:        9
 };
 
+const CT = constant_types;
+
 constant_types.LUA_TSHRSTR = constant_types.LUA_TSTRING | (0 << 4);  /* short strings */
 constant_types.LUA_TLNGSTR = constant_types.LUA_TSTRING | (1 << 4);  /* long strings */
 
@@ -62,6 +69,25 @@ constant_types.LUA_TLCL = constant_types.LUA_TFUNCTION | (0 << 4);  /* Lua closu
 constant_types.LUA_TLCF = constant_types.LUA_TFUNCTION | (1 << 4);  /* light C function */
 constant_types.LUA_TCCL = constant_types.LUA_TFUNCTION | (2 << 4);  /* C closure */
 
+/*
+** Comparison and arithmetic functions
+*/
+
+const LUA_OPADD  = 0;   /* ORDER TM, ORDER OP */
+const LUA_OPSUB  = 1;
+const LUA_OPMUL  = 2;
+const LUA_OPMOD  = 3;
+const LUA_OPPOW  = 4;
+const LUA_OPDIV  = 5;
+const LUA_OPIDIV = 6;
+const LUA_OPBAND = 7;
+const LUA_OPBOR  = 8;
+const LUA_OPBXOR = 9;
+const LUA_OPSHL  = 10;
+const LUA_OPSHR  = 11;
+const LUA_OPUNM  = 12;
+const LUA_OPBNOT = 13;
+
 const LUA_OPEQ = 0;
 const LUA_OPLT = 1;
 const LUA_OPLE = 2;
@@ -87,25 +113,26 @@ const print_version = function() {
 class lua_Debug {
 
     constructor() {
-        // int event;
-        // const char *name;   /* (n) */
-        // const char *namewhat;   /* (n) 'global', 'local', 'field', 'method' */
-        // const char *what;   /* (S) 'Lua', 'C', 'main', 'tail' */
-        // const char *source; /* (S) */
-        // int currentline;    /* (l) */
-        // int linedefined;    /* (S) */
-        // int lastlinedefined;    /* (S) */
-        // unsigned char nups; /* (u) number of upvalues */
-        // unsigned char nparams;/* (u) number of parameters */
-        // char isvararg;        /* (u) */
-        // char istailcall;    /* (t) */
-        // char short_src[LUA_IDSIZE]; /* (S) */
+        this.event = NaN;
+        this.name = null;           /* (n) */
+        this.namewhat = null;       /* (n) 'global', 'local', 'field', 'method' */
+        this.what = null;           /* (S) 'Lua', 'C', 'main', 'tail' */
+        this.source = null;         /* (S) */
+        this.currentline = NaN;     /* (l) */
+        this.linedefined = NaN;     /* (S) */
+        this.lastlinedefined = NaN; /* (S) */
+        this.nups = NaN;            /* (u) number of upvalues */
+        this.nparams = NaN;         /* (u) number of parameters */
+        this.isvararg = NaN;        /* (u) */
+        this.istailcall = NaN;      /* (t) */
+        this.short_src = null;      /* (S) */
         /* private part */
-        // struct CallInfo *i_ci;  /* active function */
+        this.i_ci = null;           /* active function */
     }
 
 }
 
+module.exports.CT                      = CT;
 module.exports.FENGARI_AUTHORS         = FENGARI_AUTHORS;
 module.exports.FENGARI_COPYRIGHT       = FENGARI_COPYRIGHT;
 module.exports.FENGARI_RELEASE         = FENGARI_RELEASE;
@@ -121,19 +148,35 @@ module.exports.LUA_INIT_VAR            = LUA_INIT_VAR;
 module.exports.LUA_MINSTACK            = LUA_MINSTACK;
 module.exports.LUA_MULTRET             = -1;
 module.exports.LUA_NUMTAGS             = LUA_NUMTAGS;
+module.exports.LUA_OPADD               = LUA_OPADD;
+module.exports.LUA_OPBAND              = LUA_OPBAND;
+module.exports.LUA_OPBNOT              = LUA_OPBNOT;
+module.exports.LUA_OPBOR               = LUA_OPBOR;
+module.exports.LUA_OPBXOR              = LUA_OPBXOR;
+module.exports.LUA_OPDIV               = LUA_OPDIV;
 module.exports.LUA_OPEQ                = LUA_OPEQ;
+module.exports.LUA_OPIDIV              = LUA_OPIDIV;
 module.exports.LUA_OPLE                = LUA_OPLE;
 module.exports.LUA_OPLT                = LUA_OPLT;
+module.exports.LUA_OPMOD               = LUA_OPMOD;
+module.exports.LUA_OPMUL               = LUA_OPMUL;
+module.exports.LUA_OPPOW               = LUA_OPPOW;
+module.exports.LUA_OPSHL               = LUA_OPSHL;
+module.exports.LUA_OPSHR               = LUA_OPSHR;
+module.exports.LUA_OPSUB               = LUA_OPSUB;
+module.exports.LUA_OPUNM               = LUA_OPUNM;
 module.exports.LUA_REGISTRYINDEX       = LUA_REGISTRYINDEX;
 module.exports.LUA_RELEASE             = LUA_RELEASE;
 module.exports.LUA_RIDX_GLOBALS        = LUA_RIDX_GLOBALS;
 module.exports.LUA_RIDX_LAST           = LUA_RIDX_LAST;
 module.exports.LUA_RIDX_MAINTHREAD     = LUA_RIDX_MAINTHREAD;
+module.exports.LUA_SIGNATURE           = LUA_SIGNATURE;
 module.exports.LUA_VERSION             = LUA_VERSION;
 module.exports.LUA_VERSION_MAJOR       = LUA_VERSION_MAJOR;
 module.exports.LUA_VERSION_MINOR       = LUA_VERSION_MINOR;
 module.exports.LUA_VERSION_NUM         = LUA_VERSION_NUM;
 module.exports.LUA_VERSION_RELEASE     = LUA_VERSION_RELEASE;
+module.exports.LUA_VERSUFFIX           = LUA_VERSUFFIX;
 module.exports.constant_types          = constant_types;
 module.exports.lua_Debug               = lua_Debug;
 module.exports.lua_upvalueindex        = lua_upvalueindex;
diff --git a/src/lualib.js b/src/lualib.js
index d87cfbc..da9b290 100644
--- a/src/lualib.js
+++ b/src/lualib.js
@@ -2,21 +2,17 @@
 "use strict";
 
 const assert = require('assert');
-const lua    = require('./lua.js');
-
-
-const LUA_VERSUFFIX = "_" + lua.LUA_VERSION_MAJOR + "_" + lua.LUA_VERSION_MINOR;
 
 const LUA_COLIBNAME   = "coroutine";
-const LUA_TABLIBNAME  = "table"
-const LUA_IOLIBNAME   = "io"
-const LUA_OSLIBNAME   = "os"
-const LUA_STRLIBNAME  = "string"
-const LUA_UTF8LIBNAME = "utf8"
-const LUA_BITLIBNAME  = "bit32"
-const LUA_MATHLIBNAME = "math"
-const LUA_DBLIBNAME   = "debug"
-const LUA_LOADLIBNAME = "package"
+const LUA_TABLIBNAME  = "table";
+const LUA_IOLIBNAME   = "io";
+const LUA_OSLIBNAME   = "os";
+const LUA_STRLIBNAME  = "string";
+const LUA_UTF8LIBNAME = "utf8";
+const LUA_BITLIBNAME  = "bit32";
+const LUA_MATHLIBNAME = "math";
+const LUA_DBLIBNAME   = "debug";
+const LUA_LOADLIBNAME = "package";
 
 
 module.exports.LUA_BITLIBNAME  = LUA_BITLIBNAME;
@@ -28,5 +24,4 @@ module.exports.LUA_MATHLIBNAME = LUA_MATHLIBNAME;
 module.exports.LUA_OSLIBNAME   = LUA_OSLIBNAME;
 module.exports.LUA_STRLIBNAME  = LUA_STRLIBNAME;
 module.exports.LUA_TABLIBNAME  = LUA_TABLIBNAME;
-module.exports.LUA_UTF8LIBNAME = LUA_UTF8LIBNAME;
-module.exports.LUA_VERSUFFIX   = LUA_VERSUFFIX;
\ No newline at end of file
+module.exports.LUA_UTF8LIBNAME = LUA_UTF8LIBNAME;
\ No newline at end of file
diff --git a/src/lundump.js b/src/lundump.js
index b79e6ea..5a6d8c4 100644
--- a/src/lundump.js
+++ b/src/lundump.js
@@ -5,6 +5,7 @@ const DataView       = require('buffer-dataview');
 const fs             = require('fs');
 const assert         = require('assert');
 
+const lua            = require('./lua.js');
 const LClosure       = require('./lobject.js').LClosure;
 const TValue         = require('./lobject.js').TValue;
 const Proto          = require('./lfunc.js').Proto;
@@ -256,7 +257,7 @@ class BytecodeParser {
     }
 
     checkHeader() {
-        if (this.readString(4) !== "\x1bLua")
+        if (this.readString(4) !== lua.LUA_SIGNATURE)
             throw new Error("bad LUA_SIGNATURE, expected '<esc>Lua'");
 
         if (this.readByte() !== 0x53)
diff --git a/src/lvm.js b/src/lvm.js
index d987cc1..0ff433e 100644
--- a/src/lvm.js
+++ b/src/lvm.js
@@ -792,6 +792,10 @@ const luaV_equalobj = function(L, t1, t2) {
     return L.stack[L.top].l_isfalse() ? 0 : 1;
 };
 
+const luaV_rawequalobj = function(t1, t2) {
+    return luaV_equalobj(null, t1, t2);
+};
+
 const forlimit = function(obj, step) {
     let stopnow = false;
     let ilimit = luaV_tointeger(obj, step < 0 ? 2 : 1);
@@ -818,9 +822,9 @@ const forlimit = function(obj, step) {
 
 /*
 ** try to convert a value to an integer, rounding according to 'mode':
-** mode == 0: accepts only integral values
-** mode == 1: takes the floor of the number
-** mode == 2: takes the ceil of the number
+** mode === 0: accepts only integral values
+** mode === 1: takes the floor of the number
+** mode === 2: takes the ceil of the number
 */
 const luaV_tointeger = function(obj, mode) {
     if (obj.ttisfloat()) {
@@ -831,7 +835,7 @@ const luaV_tointeger = function(obj, mode) {
             if (mode === 0)
                 return false;  /* fails if mode demands integral value */
             else if (mode > 1)  /* needs ceil? */
-                f += 1;  /* convert floor to ceil (remember: n != f) */
+                f += 1;  /* convert floor to ceil (remember: n !== f) */
         }
 
         return f|0;
@@ -1072,29 +1076,30 @@ const luaV_finishset = function(L, t, key, val, slot, recur) {
 }
 
 
-module.exports.dojump         = dojump;
-module.exports.donextjump     = donextjump;
-module.exports.forlimit       = forlimit;
-module.exports.gettable       = gettable;
-module.exports.l_strcmp       = l_strcmp;
-module.exports.LEintfloat     = LEintfloat;
-module.exports.LEnum          = LEnum;
-module.exports.LTintfloat     = LTintfloat;
-module.exports.LTnum          = LTnum;
-module.exports.luaV_concat    = luaV_concat;
-module.exports.luaV_equalobj  = luaV_equalobj;
-module.exports.luaV_execute   = luaV_execute;
-module.exports.luaV_finishOp  = luaV_finishOp;
-module.exports.luaV_finishset = luaV_finishset;
-module.exports.luaV_lessequal = luaV_lessequal;
-module.exports.luaV_lessthan  = luaV_lessthan;
-module.exports.luaV_objlen    = luaV_objlen;
-module.exports.luaV_tointeger = luaV_tointeger;
-module.exports.RA             = RA;
-module.exports.RB             = RB;
-module.exports.RC             = RC;
-module.exports.RKB            = RKB;
-module.exports.RKC            = RKC;
-module.exports.settable       = settable;
-module.exports.tointeger      = tointeger;
-module.exports.tonumber       = tonumber;
\ No newline at end of file
+module.exports.LEintfloat        = LEintfloat;
+module.exports.LEnum             = LEnum;
+module.exports.LTintfloat        = LTintfloat;
+module.exports.LTnum             = LTnum;
+module.exports.RA                = RA;
+module.exports.RB                = RB;
+module.exports.RC                = RC;
+module.exports.RKB               = RKB;
+module.exports.RKC               = RKC;
+module.exports.dojump            = dojump;
+module.exports.donextjump        = donextjump;
+module.exports.forlimit          = forlimit;
+module.exports.gettable          = gettable;
+module.exports.l_strcmp          = l_strcmp;
+module.exports.luaV_concat       = luaV_concat;
+module.exports.luaV_equalobj     = luaV_equalobj;
+module.exports.luaV_execute      = luaV_execute;
+module.exports.luaV_finishOp     = luaV_finishOp;
+module.exports.luaV_finishset    = luaV_finishset;
+module.exports.luaV_lessequal    = luaV_lessequal;
+module.exports.luaV_lessthan     = luaV_lessthan;
+module.exports.luaV_objlen       = luaV_objlen;
+module.exports.luaV_rawequalobj = luaV_rawequalobj;
+module.exports.luaV_tointeger    = luaV_tointeger;
+module.exports.settable          = settable;
+module.exports.tointeger         = tointeger;
+module.exports.tonumber          = tonumber;
\ No newline at end of file
diff --git a/tests/lapi.js b/tests/lapi.js
index 30366d5..c422ada 100644
--- a/tests/lapi.js
+++ b/tests/lapi.js
@@ -1,4 +1,3 @@
-/*jshint esversion: 6 */
 "use strict";
 
 const test       = require('tape');
@@ -330,7 +329,7 @@ test('lua_pcall that breaks', function (t) {
     t.doesNotThrow(function () {
 
         let fn = function(L) {
-            return undefined_value;
+            return "undefined_value";
         };
 
         L = lauxlib.luaL_newstate();
@@ -383,7 +382,7 @@ test('lua_load and lua_call it', function (t) {
 
         L = lauxlib.luaL_newstate();
 
-        lapi.lua_load(L, bc, "test-lua_load")
+        lapi.lua_load(L, null, bc, "test-lua_load", "binary");
 
         lapi.lua_call(L, 0, 1);
 
@@ -410,7 +409,7 @@ test('lua script reads js upvalues', function (t) {
 
         L = lauxlib.luaL_newstate();
 
-        lapi.lua_load(L, bc, "test-lua_load")
+        lapi.lua_load(L, null, bc, "test-lua_load", "binary");
 
         lapi.lua_pushstring(L, "hello");
         lapi.lua_setglobal(L, "js");
diff --git a/tests/lbaselib.js b/tests/lbaselib.js
index be5cdad..be741dc 100644
--- a/tests/lbaselib.js
+++ b/tests/lbaselib.js
@@ -1,4 +1,3 @@
-/*jshint esversion: 6 */
 "use strict";
 
 const test       = require('tape');
@@ -32,7 +31,7 @@ test('print', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-print");
+        lapi.lua_load(L, null, bc, "test-print", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -66,7 +65,7 @@ test('setmetatable, getmetatable', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-setmetatable-getmetatable");
+        lapi.lua_load(L, null, bc, "test-setmetatable-getmetatable", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -111,7 +110,7 @@ test('rawequal', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-rawequal");
+        lapi.lua_load(L, null, bc, "test-rawequal", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -157,7 +156,7 @@ test('rawset, rawget', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-rawequal");
+        lapi.lua_load(L, null, bc, "test-rawequal", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -204,7 +203,7 @@ test('type', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-type");
+        lapi.lua_load(L, null, bc, "test-type", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -257,7 +256,7 @@ test('error', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-error");
+        lapi.lua_load(L, null, bc, "test-error", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -280,7 +279,7 @@ test('error, protected', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-error");
+        lapi.lua_load(L, null, bc, "test-error", "binary");
 
         lapi.lua_pcall(L, 0, -1, 0);
 
@@ -312,7 +311,7 @@ test('pcall', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-pcall");
+        lapi.lua_load(L, null, bc, "test-pcall", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -348,7 +347,7 @@ test('xpcall', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-pcall");
+        lapi.lua_load(L, null, bc, "test-pcall", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -390,7 +389,7 @@ test('ipairs', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-ipairs");
+        lapi.lua_load(L, null, bc, "test-ipairs", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -419,7 +418,7 @@ test('select', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-select");
+        lapi.lua_load(L, null, bc, "test-select", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -460,7 +459,7 @@ test('tonumber', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-tonumber");
+        lapi.lua_load(L, null, bc, "test-tonumber", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -507,7 +506,7 @@ test('assert', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-assert");
+        lapi.lua_load(L, null, bc, "test-assert", "binary");
 
         lapi.lua_pcall(L, 0, -1, 0);
 
@@ -535,7 +534,7 @@ test('rawlen', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-rawlen");
+        lapi.lua_load(L, null, bc, "test-rawlen", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -582,7 +581,7 @@ test('next', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-next");
+        lapi.lua_load(L, null, bc, "test-next", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -623,7 +622,7 @@ test('pairs', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-pairs");
+        lapi.lua_load(L, null, bc, "test-pairs", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -673,7 +672,7 @@ test('pairs with __pairs', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-pairs");
+        lapi.lua_load(L, null, bc, "test-pairs", "binary");
 
         lapi.lua_call(L, 0, -1);
 
diff --git a/tests/lcorolib.js b/tests/lcorolib.js
index 78024dd..9c1d9b1 100644
--- a/tests/lcorolib.js
+++ b/tests/lcorolib.js
@@ -1,4 +1,3 @@
-/*jshint esversion: 6 */
 "use strict";
 
 const test       = require('tape');
@@ -41,7 +40,7 @@ test('coroutine.create, coroutine.yield, coroutine.resume', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-coroutine");
+        lapi.lua_load(L, null, bc, "test-coroutine", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -84,7 +83,7 @@ test('coroutine.status', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-coroutine.status");
+        lapi.lua_load(L, null, bc, "test-coroutine.status", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -125,7 +124,7 @@ test('coroutine.isyieldable', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-coroutine.isyieldable");
+        lapi.lua_load(L, null, bc, "test-coroutine.isyieldable", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -166,7 +165,7 @@ test('coroutine.running', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-coroutine.running");
+        lapi.lua_load(L, null, bc, "test-coroutine.running", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -207,7 +206,7 @@ test('coroutine.wrap', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-coroutine.wrap");
+        lapi.lua_load(L, null, bc, "test-coroutine.wrap", "binary");
 
         lapi.lua_call(L, 0, -1);
 
diff --git a/tests/ldebug.js b/tests/ldebug.js
index 491b8ba..472c66b 100644
--- a/tests/ldebug.js
+++ b/tests/ldebug.js
@@ -1,4 +1,3 @@
-/*jshint esversion: 6 */
 "use strict";
 
 const test       = require('tape');
@@ -31,7 +30,7 @@ test('luaG_typeerror', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-typeerror");
+        lapi.lua_load(L, null, bc, "test-typeerror", "binary");
 
         lapi.lua_pcall(L, 0, -1, 0);
 
@@ -61,7 +60,7 @@ test('luaG_typeerror', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-typeerror");
+        lapi.lua_load(L, null, bc, "test-typeerror", "binary");
 
         lapi.lua_pcall(L, 0, -1, 0);
 
@@ -90,7 +89,7 @@ test('luaG_typeerror', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-typeerror");
+        lapi.lua_load(L, null, bc, "test-typeerror", "binary");
 
         lapi.lua_pcall(L, 0, -1, 0);
 
@@ -119,7 +118,7 @@ test('luaG_typeerror', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-typeerror");
+        lapi.lua_load(L, null, bc, "test-typeerror", "binary");
 
         lapi.lua_pcall(L, 0, -1, 0);
 
@@ -147,7 +146,7 @@ test('luaG_concaterror', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-typeerror");
+        lapi.lua_load(L, null, bc, "test-typeerror", "binary");
 
         lapi.lua_pcall(L, 0, -1, 0);
 
@@ -175,7 +174,7 @@ test('luaG_opinterror', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-typeerror");
+        lapi.lua_load(L, null, bc, "test-typeerror", "binary");
 
         lapi.lua_pcall(L, 0, -1, 0);
 
@@ -203,7 +202,7 @@ test('luaG_tointerror', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-typeerror");
+        lapi.lua_load(L, null, bc, "test-typeerror", "binary");
 
         lapi.lua_pcall(L, 0, -1, 0);
 
diff --git a/tests/lexparse.js b/tests/lexparse.js
new file mode 100644
index 0000000..0d9c51d
--- /dev/null
+++ b/tests/lexparse.js
@@ -0,0 +1,40 @@
+"use strict";
+
+const test       = require('tape');
+const beautify   = require('js-beautify').js_beautify;
+
+const tests      = require("./tests.js");
+const toByteCode = tests.toByteCode;
+
+const lapi       = require("../src/lapi.js");
+const lauxlib    = require("../src/lauxlib.js");
+const linit      = require('../src/linit.js');
+
+
+test('LOADK, RETURN', function (t) {
+    let luaCode = `
+        local a = "hello world"
+        return a
+    `, L;
+    
+    t.plan(2);
+
+    t.doesNotThrow(function () {
+
+        L = lauxlib.luaL_newstate();
+
+        linit.luaL_openlibs(L);
+
+        lapi.lua_load(L, null, luaCode, "test", "text");
+
+        lapi.lua_call(L, 0, -1);
+
+    }, "JS Lua program ran without error");
+
+    t.strictEqual(
+        lapi.lua_tostring(L, -1),
+        "hello world",
+        "Correct element(s) on the stack"
+    );
+
+});
\ No newline at end of file
diff --git a/tests/llex.js b/tests/llex.js
new file mode 100644
index 0000000..8b69acc
--- /dev/null
+++ b/tests/llex.js
@@ -0,0 +1,97 @@
+"use strict";
+
+const test     = require('tape');
+const beautify = require('js-beautify').js_beautify;
+
+const tests    = require("./tests.js");
+
+const lapi     = require("../src/lapi.js");
+const lauxlib  = require("../src/lauxlib.js");
+const llex     = require("../src/llex.js");
+const lua      = require('../src/lua.js');
+const R        = llex.RESERVED;
+
+
+test('basic lexing: TK_RETURN, TK_STRING', function (t) {
+    let luaCode = `
+        return "hello lex !"
+    `, L;
+    
+    t.plan(2);
+
+    let readTokens = [];
+
+    t.doesNotThrow(function () {
+
+        L = lauxlib.luaL_newstate();
+
+        let ls = new llex.LexState();
+        llex.luaX_setinput(L, ls, new llex.MBuffer(luaCode), luaCode, luaCode.charAt(0));
+
+        llex.luaX_next(ls);
+
+        while (ls.t.token !== R.TK_EOS) {
+            // console.log(llex.luaX_tokens[ls.t.token - llex.FIRST_RESERVED]);
+
+            readTokens.push(ls.t.token);
+            llex.luaX_next(ls);
+        }
+
+
+    }, "JS Lua program ran without error");
+
+    t.deepEqual(
+        readTokens,
+        [R.TK_RETURN, R.TK_STRING],
+        "Correct tokens found"
+    );
+
+});
+
+
+test('TK_LOCAL, TK_NAME, TK_INT', function (t) {
+    let luaCode = `
+        local f = testing(aBunch)
+            return "of"
+        end
+
+        return f("things") + 12
+    `, L;
+    
+    t.plan(2);
+
+    let readTokens = [];
+
+    t.doesNotThrow(function () {
+
+        L = lauxlib.luaL_newstate();
+
+        let ls = new llex.LexState();
+        llex.luaX_setinput(L, ls, new llex.MBuffer(luaCode), luaCode, luaCode.charAt(0));
+
+        llex.luaX_next(ls);
+
+        while (ls.t.token !== R.TK_EOS) {
+            // console.log(ls.t.token >= llex.FIRST_RESERVED ?
+            //         llex.luaX_tokens[ls.t.token - llex.FIRST_RESERVED]
+            //         : ls.t.token);
+
+            readTokens.push(ls.t.token);
+            llex.luaX_next(ls);
+        }
+
+
+    }, "JS Lua program ran without error");
+
+    t.deepEqual(
+        readTokens,
+        [
+            R.TK_LOCAL, R.TK_NAME, '=', R.TK_NAME, '(', R.TK_NAME, ')',
+                R.TK_RETURN, R.TK_STRING,
+            R.TK_END,
+            R.TK_RETURN, R.TK_NAME, '(', R.TK_STRING, ')', '+', R.TK_INT
+        ],
+        "Correct tokens found"
+    );
+
+});
\ No newline at end of file
diff --git a/tests/lmathlib.js b/tests/lmathlib.js
index ba6853c..ae0c40b 100644
--- a/tests/lmathlib.js
+++ b/tests/lmathlib.js
@@ -1,4 +1,3 @@
-/*jshint esversion: 6 */
 "use strict";
 
 const test       = require('tape');
@@ -34,7 +33,7 @@ test('math.abs, math.sin, math.cos, math.tan, math.asin, math.acos, math.atan',
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-math");
+        lapi.lua_load(L, null, bc, "test-math", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -99,7 +98,7 @@ test('math.ceil, math.floor', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-math");
+        lapi.lua_load(L, null, bc, "test-math", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -135,7 +134,7 @@ test('math.deg, math.rad', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-math");
+        lapi.lua_load(L, null, bc, "test-math", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -171,7 +170,7 @@ test('math.log', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-math");
+        lapi.lua_load(L, null, bc, "test-math", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -213,7 +212,7 @@ test('math.exp', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-math");
+        lapi.lua_load(L, null, bc, "test-math", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -243,7 +242,7 @@ test('math.min, math.max', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-math");
+        lapi.lua_load(L, null, bc, "test-math", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -279,7 +278,7 @@ test('math.random', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-math");
+        lapi.lua_load(L, null, bc, "test-math", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -313,7 +312,7 @@ test('math.sqrt', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-math");
+        lapi.lua_load(L, null, bc, "test-math", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -343,7 +342,7 @@ test('math.tointeger', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-math");
+        lapi.lua_load(L, null, bc, "test-math", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -373,7 +372,7 @@ test('math.type', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-math");
+        lapi.lua_load(L, null, bc, "test-math", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -415,7 +414,7 @@ test('math.ult', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-math");
+        lapi.lua_load(L, null, bc, "test-math", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -445,7 +444,7 @@ test('math.fmod', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-math");
+        lapi.lua_load(L, null, bc, "test-math", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -475,7 +474,7 @@ test('math.modf', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-math");
+        lapi.lua_load(L, null, bc, "test-math", "binary");
 
         lapi.lua_call(L, 0, -1);
 
diff --git a/tests/load.js b/tests/load.js
new file mode 100644
index 0000000..a71de6b
--- /dev/null
+++ b/tests/load.js
@@ -0,0 +1,68 @@
+"use strict";
+
+const test       = require('tape');
+const beautify   = require('js-beautify').js_beautify;
+
+const tests      = require("./tests.js");
+const toByteCode = tests.toByteCode;
+
+const lapi       = require("../src/lapi.js");
+const lauxlib    = require("../src/lauxlib.js");
+const linit      = require('../src/linit.js');
+
+test('lua_load, binary mode', function (t) {
+    let luaCode = `
+        return "hello world"
+    `, L;
+    
+    t.plan(2);
+
+    t.doesNotThrow(function () {
+
+        let bc = toByteCode(luaCode).dataView;
+
+        L = lauxlib.luaL_newstate();
+
+        linit.luaL_openlibs(L);
+
+        lapi.lua_load(L, null, bc, "test-load", "binary");
+
+        lapi.lua_call(L, 0, -1);
+
+    }, "JS Lua program ran without error");
+
+    t.strictEqual(
+        lapi.lua_tostring(L, -1),
+        "hello world",
+        "Correct element(s) on the stack"
+    );
+
+});
+
+
+test('lua_load, text mode', function (t) {
+    let luaCode = `
+        return "hello world"
+    `, L;
+    
+    t.plan(2);
+
+    t.doesNotThrow(function () {
+
+        L = lauxlib.luaL_newstate();
+
+        linit.luaL_openlibs(L);
+
+        lapi.lua_load(L, null, luaCode, "test-load", "text");
+
+        lapi.lua_call(L, 0, -1);
+
+    }, "JS Lua program ran without error");
+
+    t.strictEqual(
+        lapi.lua_tostring(L, -1),
+        "hello world",
+        "Correct element(s) on the stack"
+    );
+
+});
\ No newline at end of file
diff --git a/tests/ltablib.js b/tests/ltablib.js
index fa15d6a..c8a1e73 100644
--- a/tests/ltablib.js
+++ b/tests/ltablib.js
@@ -1,4 +1,3 @@
-/*jshint esversion: 6 */
 "use strict";
 
 const test       = require('tape');
@@ -43,7 +42,7 @@ test('table.concat', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-table.concat");
+        lapi.lua_load(L, null, bc, "test-table.concat", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -72,7 +71,7 @@ test('table.pack', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-table.pack");
+        lapi.lua_load(L, null, bc, "test-table.pack", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -103,7 +102,7 @@ test('table.unpack', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-table.unpack");
+        lapi.lua_load(L, null, bc, "test-table.unpack", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -147,7 +146,7 @@ test('table.insert', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-table.insert");
+        lapi.lua_load(L, null, bc, "test-table.insert", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -181,7 +180,7 @@ test('table.remove', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-table.remove");
+        lapi.lua_load(L, null, bc, "test-table.remove", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -214,7 +213,7 @@ test('table.move', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-table.move");
+        lapi.lua_load(L, null, bc, "test-table.move", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -247,7 +246,7 @@ test('table.sort (<)', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-table.sort");
+        lapi.lua_load(L, null, bc, "test-table.sort", "binary");
 
         lapi.lua_call(L, 0, -1);
 
@@ -280,7 +279,7 @@ test('table.sort with cmp function', function (t) {
 
         linit.luaL_openlibs(L);
 
-        lapi.lua_load(L, bc, "test-table.sort");
+        lapi.lua_load(L, null, bc, "test-table.sort", "binary");
 
         lapi.lua_call(L, 0, -1);
 
diff --git a/tests/ltm.js b/tests/ltm.js
index a05d2b5..d749d7b 100644
--- a/tests/ltm.js
+++ b/tests/ltm.js
@@ -1,4 +1,3 @@
-/*jshint esversion: 6 */
 "use strict";
 
 const test     = require('tape');
diff --git a/tests/lvm.js b/tests/lvm.js
index 4f02ed5..5b5deac 100644
--- a/tests/lvm.js
+++ b/tests/lvm.js
@@ -1,4 +1,3 @@
-/*jshint esversion: 6 */
 "use strict";
 
 const test           = require('tape');
@@ -7,7 +6,7 @@ const beautify       = require('js-beautify').js_beautify;
 const lua_State      = require("../src/lstate.js").lua_State;
 const VM             = require("../src/lvm.js");
 const lapi           = require("../src/lapi.js");
-const Table          = require("../src/lobject.js").Table;;
+const Table          = require("../src/lobject.js").Table;
 
 const getState       = require("./tests.js").getState;
 
diff --git a/tests/tests.js b/tests/tests.js
index 0963159..a47aee5 100644
--- a/tests/tests.js
+++ b/tests/tests.js
@@ -1,4 +1,3 @@
-/*jshint esversion: 6 */
 "use strict";
 
 const fs             = require('fs');