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Diffstat (limited to 'src/lparser.js')
-rw-r--r--src/lparser.js685
1 files changed, 685 insertions, 0 deletions
diff --git a/src/lparser.js b/src/lparser.js
index a7e4209..154310b 100644
--- a/src/lparser.js
+++ b/src/lparser.js
@@ -61,6 +61,10 @@ const expkind = {
VVARARG: 14 /* vararg expression; info = instruction pc */
};
+const vkisvar = function(k) {
+ return expkind.VLOCAL <= k && k <= expkind.VINDEXED;
+};
+
class expdesc {
constructor() {
this.k = NaN;
@@ -174,18 +178,53 @@ 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].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++].idx = reg;
+};
+
+const new_localvarliteral = function(ls, name) {
+ new_localvar(ls, new TValue(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 === name)
+ return i;
+ }
+ return -1; /* not found */
+};
+
const newupvalue = function(fs, name, v) {
let f = fs.f;
checklimit(fs, fs.nups + 1, lfunc.MAXUPVAL, "upvalues");
@@ -196,6 +235,86 @@ const newupvalue = function(fs, name, v) {
return fs.nups++;
};
+const searchvar = function(fs, n) {
+ for (let i = fs.nactvar - 1; i >= 0; i--) {
+ if (n === getlocvar(fs, i).varname)
+ 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;
@@ -321,6 +440,27 @@ const undefgoto = function(ls, gt) {
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) {
this.f = new Proto();
fs.prev = ls.fs; /* linked list of funcstates */
@@ -402,6 +542,16 @@ const statlist = function(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 '[' */
@@ -523,12 +673,176 @@ const constructor = function(ls, t) {
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 */
@@ -668,6 +982,278 @@ 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(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 === ll.arr[i].name) {
+ 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();
@@ -715,6 +1301,105 @@ const ifstat = function(ls, 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);
generated by cgit v1.2.3-70-g09d2 (git 2.47.0) at 2024-11-11 01:57:47 +0000