diff options
Diffstat (limited to 'src/ste/Transcompiler.php')
| -rw-r--r-- | src/ste/Transcompiler.php | 456 |
1 files changed, 456 insertions, 0 deletions
diff --git a/src/ste/Transcompiler.php b/src/ste/Transcompiler.php new file mode 100644 index 0000000..4988624 --- /dev/null +++ b/src/ste/Transcompiler.php @@ -0,0 +1,456 @@ +<?php + +// File: Transcompiler.php + +// Namespace: kch42\ste +namespace kch42\ste; + +/* + * Class: Transcompiler + * Contains the STE transcompiler. You'll only need this, if you want to manually transcompile a STE template. + */ +class Transcompiler { + private static $builtins = NULL; + + public static function tempvar($typ) { + return $typ . '_' . str_replace('.', '_', uniqid('', true)); + } + + public static function init_builtins() { + if(self::$builtins !== NULL) { + return; + } + + self::$builtins = array( + "if" => function($ast) { + $output = ""; + $condition = array(); + $then = NULL; + $else = NULL; + + foreach($ast->sub as $node) { + if(($node instanceof TagNode) and ($node->name == "then")) { + $then = $node->sub; + } else if(($node instanceof TagNode) and ($node->name == "else")) { + $else = $node->sub; + } else { + $condition[] = $node; + } + } + + if($then === NULL) { + throw new ParseCompileError("self::Transcompile error: Missing <ste:then> in <ste:if>.", $ast->tpl, $ast->offset); + } + + $output .= "\$outputstack[] = \"\";\n\$outputstack_i++;\n"; + $output .= self::_transcompile($condition); + $output .= "\$outputstack_i--;\nif(\$ste->evalbool(array_pop(\$outputstack)))\n{\n"; + $output .= self::indent_code(self::_transcompile($then)); + $output .= "\n}\n"; + if($else !== NULL) { + $output .= "else\n{\n"; + $output .= self::indent_code(self::_transcompile($else)); + $output .= "\n}\n"; + } + return $output; + }, + "cmp" => function($ast) { + $operators = array( + array('eq', '=='), + array('neq', '!='), + array('lt', '<'), + array('lte', '<='), + array('gt', '>'), + array('gte', '>=') + ); + + $code = ""; + + if(isset($ast->params["var_b"])) { + list($val, $pre) = self::_transcompile($ast->params["var_b"], true); + $code .= $pre; + $b = '$ste->get_var_by_name(' . $val . ')'; + } else if(isset($ast->params["text_b"])) { + list($b, $pre) = self::_transcompile($ast->params["text_b"], true); + $code .= $pre; + } else { + throw new ParseCompileError("self::Transcompile error: neiter var_b nor text_b set in <ste:cmp>.", $ast->tpl, $ast->offset); + } + + if(isset($ast->params["var_a"])) { + list($val, $pre) = self::_transcompile($ast->params["var_a"], true); + $code .= $pre; + $a = '$ste->get_var_by_name(' . $val . ')'; + } else if(isset($ast->params["text_a"])) { + list($a, $pre) = self::_transcompile($ast->params["text_a"], true); + $code .= $pre; + } else { + throw new ParseCompileError("self::Transcompile error: neiter var_a nor text_a set in <ste:cmp>.", $ast->tpl, $ast->offset); + } + + if(!isset($ast->params["op"])) { + throw new ParseCompileError("self::Transcompile error: op not given in <ste:cmp>.", $ast->tpl, $ast->offset); + } + if((count($ast->params["op"]) == 1) and ($ast->params["op"][0] instanceof TextNode)) { + /* Operator is known at compile time, this saves *a lot* of output code! */ + $op = trim($ast->params["op"][0]->text); + $op_php = NULL; + foreach($operators as $v) { + if($v[0] == $op) { + $op_php = $v[1]; + break; + } + } + if($op_php === NULL) { + throw new ParseCompileError("self::Transcompile Error: Unknown operator in <ste:cmp>", $ast->tpl, $ast->offset); + } + $code .= "\$outputstack[\$outputstack_i] .= (($a) $op_php ($b)) ? 'yes' : '';\n"; + } else { + list($val, $pre) = self::_transcompile($ast->params["op"], true); + $code .= $pre . "switch(trim(" . $val . "))\n{\n\t"; + $code .= implode("", array_map( + function($op) use ($a,$b) + { + list($op_stetpl, $op_php) = $op; + return "case '$op_stetpl':\n\t\$outputstack[\$outputstack_i] .= (($a) $op_php ($b)) ? 'yes' : '';\n\tbreak;\n\t"; + }, $operators + )); + $code .= "default: throw new \\kch42\\ste\\RuntimeError('Unknown operator in <ste:cmp>.');\n}\n"; + } + return $code; + }, + "not" => function($ast) { + $code = "\$outputstack[] = '';\n\$outputstack_i++;\n"; + $code .= self::_transcompile($ast->sub); + $code .= "\$outputstack_i--;\n\$outputstack[\$outputstack_i] .= (!\$ste->evalbool(array_pop(\$outputstack))) ? 'yes' : '';\n"; + return $code; + }, + "even" => function($ast) { + $code = "\$outputstack[] = '';\n\$outputstack_i++;\n"; + $code .= self::_transcompile($ast->sub); + $code .= "\$outputstack_i--;\n\$tmp_even = array_pop(\$outputstack);\n\$outputstack[\$outputstack_i] .= (is_numeric(\$tmp_even) and (\$tmp_even % 2 == 0)) ? 'yes' : '';\n"; + return $code; + }, + "for" => function($ast) { + $code = ""; + $loopname = self::tempvar("forloop"); + if(empty($ast->params["start"])) { + throw new ParseCompileError("self::Transcompile error: Missing 'start' parameter in <ste:for>.", $ast->tpl, $ast->offset); + } + list($val, $pre) = self::_transcompile($ast->params["start"], true); + $code .= $pre; + $code .= "\$${loopname}_start = " . $val . ";\n"; + + if(empty($ast->params["stop"])) { + throw new ParseCompileError("self::Transcompile error: Missing 'end' parameter in <ste:for>.", $ast->tpl, $ast->offset); + } + list($val, $pre) = self::_transcompile($ast->params["stop"], true); + $code .= $pre; + $code .= "\$${loopname}_stop = " . $val . ";\n"; + + $step = NULL; /* i.e. not known at compilation time */ + if(empty($ast->params["step"])) { + $step = 1; + } else if((count($ast->params["step"]) == 1) and ($ast->params["step"][0] instanceof TextNode)) { + $step = $ast->params["step"][0]->text + 0; + } else { + list($val, $pre) = self::_transcompile($ast->params["step"], true); + $code .= $pre; + $code .= "\$${loopname}_step = " . $val . ";\n"; + } + + if(!empty($ast->params["counter"])) { + list($val, $pre) = self::_transcompile($ast->params["counter"], true); + $code .= $pre; + $code .= "\$${loopname}_countername = " . $val . ";\n"; + } + + $loopbody = empty($ast->params["counter"]) ? "" : "\$ste->set_var_by_name(\$${loopname}_countername, \$${loopname}_counter);\n"; + $loopbody .= self::_transcompile($ast->sub); + $loopbody = self::indent_code("{\n" . self::loopbody(self::indent_code($loopbody)) . "\n}\n"); + + if($step === NULL) { + $code .= "if(\$${loopname}_step == 0)\n\tthrow new \\kch42\\ste\\RuntimeError('step can not be 0 in <ste:for>.');\n"; + $code .= "if(\$${loopname}_step > 0)\n{\n"; + $code .= "\tfor(\$${loopname}_counter = \$${loopname}_start; \$${loopname}_counter <= \$${loopname}_stop; \$${loopname}_counter += \$${loopname}_step)\n"; + $code .= $loopbody; + $code .= "\n}\nelse\n{\n"; + $code .= "\tfor(\$${loopname}_counter = \$${loopname}_start; \$${loopname}_counter >= \$${loopname}_stop; \$${loopname}_counter += \$${loopname}_step)\n"; + $code .= $loopbody; + $code .= "\n}\n"; + } else if($step == 0) { + throw new ParseCompileError("self::Transcompile Error: step can not be 0 in <ste:for>.", $ast->tpl, $ast->offset); + } else if($step > 0) { + $code .= "for(\$${loopname}_counter = \$${loopname}_start; \$${loopname}_counter <= \$${loopname}_stop; \$${loopname}_counter += $step)\n$loopbody\n"; + } else { + $code .= "for(\$${loopname}_counter = \$${loopname}_start; \$${loopname}_counter >= \$${loopname}_stop; \$${loopname}_counter += $step)\n$loopbody\n"; + } + + return $code; + }, + "foreach" => function($ast) { + $loopname = self::tempvar("foreachloop"); + $code = ""; + + if(empty($ast->params["array"])) { + throw new ParseCompileError("self::Transcompile Error: array not given in <ste:foreach>.", $ast->tpl, $ast->offset); + } + list($val, $pre) = self::_transcompile($ast->params["array"], true); + $code .= $pre; + $code .= "\$${loopname}_arrayvar = " . $val . ";\n"; + + if(empty($ast->params["value"])) { + throw new ParseCompileError("self::Transcompile Error: value not given in <ste:foreach>.", $ast->tpl, $ast->offset); + } + list($val, $pre) = self::_transcompile($ast->params["value"], true); + $code .= $pre; + $code .= "\$${loopname}_valuevar = " . $val . ";\n"; + + if(!empty($ast->params["key"])) { + list($val, $pre) = self::_transcompile($ast->params["key"], true); + $code .= $pre; + $code .= "\$${loopname}_keyvar = " . $val . ";\n"; + } + + if(!empty($ast->params["counter"])) { + list($val, $pre) = self::_transcompile($ast->params["counter"], true); + $code .= $pre; + $code .= "\$${loopname}_countervar = " . $val . ";\n"; + } + + $loopbody = ""; + $code .= "\$${loopname}_array = \$ste->get_var_by_name(\$${loopname}_arrayvar);\n"; + $code .= "if(!is_array(\$${loopname}_array))\n\t\$${loopname}_array = array();\n"; + if(!empty($ast->params["counter"])) { + $code .= "\$${loopname}_counter = -1;\n"; + $loopbody .= "\$${loopname}_counter++;\n\$ste->set_var_by_name(\$${loopname}_countervar, \$${loopname}_counter);\n"; + } + + $loop = array(); + $else = array(); + foreach($ast->sub as $node) { + if(($node instanceof TagNode) && ($node->name == "else")) { + $else = array_merge($else, $node->sub); + } else { + $loop[] = $node; + } + } + + $loopbody .= "\$ste->set_var_by_name(\$${loopname}_valuevar, \$${loopname}_value);\n"; + if(!empty($ast->params["key"])) { + $loopbody .= "\$ste->set_var_by_name(\$${loopname}_keyvar, \$${loopname}_key);\n"; + } + $loopbody .= "\n"; + $loopbody .= self::_transcompile($loop); + $loopbody = "{\n" . self::loopbody(self::indent_code($loopbody)) . "\n}\n"; + + if(!empty($else)) { + $code .= "if(empty(\$${loopname}_array))\n{\n"; + $code .= self::indent_code(self::_transcompile($else)); + $code .= "\n}\nelse "; + } + $code .= "foreach(\$${loopname}_array as \$${loopname}_key => \$${loopname}_value)\n$loopbody\n"; + + return $code; + }, + "infloop" => function($ast) { + return "while(true)\n{\n" . self::indent_code(self::loopbody(self::indent_code(self::_transcompile($ast->sub)))) . "\n}\n"; + }, + "break" => function($ast) { + return "throw new \\kch42\\ste\\BreakException();\n"; + }, + "continue" => function($ast) { + return "throw new \\kch42\\ste\\ContinueException();\n"; + }, + "block" => function($ast) { + if(empty($ast->params["name"])) { + throw new ParseCompileError("self::Transcompile Error: name missing in <ste:block>.", $ast->tpl, $ast->offset); + } + + $blknamevar = self::tempvar("blockname"); + + list($val, $code) = self::_transcompile($ast->params["name"], true); + $code .= "\$${blknamevar} = " . $val . ";\n"; + + $tmpblk = uniqid("", true); + $code .= "\$ste->blocks['$tmpblk'] = array_pop(\$outputstack);\n\$ste->blockorder[] = '$tmpblk';\n\$outputstack = array('');\n\$outputstack_i = 0;\n"; + + $code .= self::_transcompile($ast->sub); + + $code .= "\$ste->blocks[\$${blknamevar}] = array_pop(\$outputstack);\n"; + $code .= "if(array_search(\$${blknamevar}, \$ste->blockorder) === false)\n\t\$ste->blockorder[] = \$${blknamevar};\n\$outputstack = array('');\n\$outputstack_i = 0;\n"; + + return $code; + }, + "load" => function($ast) { + if(empty($ast->params["name"])) { + throw new ParseCompileError("self::Transcompile Error: name missing in <ste:load>.", $ast->tpl, $ast->offset); + } + + list($val, $code) = self::_transcompile($ast->params["name"], true); + $code .= "\$outputstack[\$outputstack_i] .= \$ste->load(" . $val . ");\n"; + return $code; + }, + "mktag" => function($ast) { + $code = ""; + + if(empty($ast->params["name"])) { + throw new ParseCompileError("self::Transcompile Error: name missing in <ste:mktag>.", $ast->tpl, $ast->offset); + } + + $fxbody = "\$outputstack = array(''); \$outputstack_i = 0;\$ste->set_local_var('_tag_parameters', \$params);\n"; + + list($tagname, $tagname_pre) = self::_transcompile($ast->params["name"], true); + + $usemandatory = ""; + if(!empty($ast->params["mandatory"])) { + $usemandatory = " use (\$mandatory_params)"; + $code .= "\$outputstack[] = '';\n\$outputstack_i++;\n"; + $code .= self::_transcompile($ast->params["mandatory"]); + $code .= "\$outputstack_i--;\n\$mandatory_params = explode('|', array_pop(\$outputstack));\n"; + + $fxbody .= "foreach(\$mandatory_params as \$mp)\n{\n\tif(!isset(\$params[\$mp]))\n\t\tthrow new \\kch42\\ste\\RuntimeError(\"\$mp missing in <ste:\" . $tagname . \">.\");\n}"; + } + + $fxbody .= self::_transcompile($ast->sub); + $fxbody .= "return array_pop(\$outputstack);"; + + $code .= "\$tag_fx = \$ste->make_closure(function(\$ste, \$params, \$sub)" . $usemandatory . "\n{\n" . self::indent_code($fxbody) . "\n});\n"; + $code .= $tagname_pre; + $code .= "\$ste->register_tag($tagname, \$tag_fx);\n"; + + return $code; + }, + "tagcontent" => function($ast) { + return "\$outputstack[\$outputstack_i] .= \$sub(\$ste);"; + }, + "set" => function($ast) { + if(empty($ast->params["var"])) { + throw new ParseCompileError("self::Transcompile Error: var missing in <ste:set>.", $ast->tpl, $ast->offset); + } + + $code = "\$outputstack[] = '';\n\$outputstack_i++;\n"; + $code .= self::_transcompile($ast->sub); + $code .= "\$outputstack_i--;\n"; + + list($val, $pre) = self::_transcompile($ast->params["var"], true); + $code .= $pre; + $code .= "\$ste->set_var_by_name(" . $val . ", array_pop(\$outputstack));\n"; + + return $code; + }, + "setlocal" => function($ast) { + if(empty($ast->params["var"])) { + throw new ParseCompileError("self::Transcompile Error: var missing in <ste:set>.", $ast->tpl, $ast->offset); + } + + $code = "\$outputstack[] = '';\n\$outputstack_i++;\n"; + $code .= self::_transcompile($ast->sub); + $code .= "\$outputstack_i--;\n"; + + list($val, $pre) = self::_transcompile($ast->params["var"], true); + $code .= $pre; + $code .= "\$ste->set_local_var(" . $val . ", array_pop(\$outputstack));\n"; + + return $code; + }, + "get" => function($ast) { + if(empty($ast->params["var"])) { + throw new ParseCompileError("self::Transcompile Error: var missing in <ste:get>.", $ast->tpl, $ast->offset); + } + + list($val, $pre) = self::_transcompile($ast->params["var"], true); + return "$pre\$outputstack[\$outputstack_i] .= \$ste->get_var_by_name(" . $val . ");"; + }, + "calc" => function($ast) { + $code = "\$outputstack[] = '';\n\$outputstack_i++;\n"; + $code .= self::_transcompile($ast->sub); + $code .= "\$outputstack_i--;\n\$outputstack[\$outputstack_i] .= \$ste->calc(array_pop(\$outputstack));\n"; + + return $code; + } + ); + } + + private static function indent_code($code) { + return implode( + "\n", + array_map(function($line) { return "\t$line"; }, explode("\n", $code)) + ); + } + + private static function loopbody($code) { + return "try\n{\n" . self::indent_code($code) . "\n}\ncatch(\\kch42\\ste\\BreakException \$e) { break; }\ncatch(\\kch42\\ste\\ContinueException \$e) { continue; }\n"; + } + + private static function _transcompile($ast, $avoid_outputstack = false) { /* The real self::transcompile function, does not add boilerplate code. */ + $code = ""; + + $text_and_var_buffer = array(); + + foreach($ast as $node) { + if($node instanceof TextNode) { + $text_and_var_buffer[] = '"' . Misc::escape_text($node->text) . '"'; + } else if($node instanceof VariableNode) { + $text_and_var_buffer[] = $node->transcompile(); + } else if($node instanceof TagNode) { + if(!empty($text_and_var_buffer)) { + $code .= "\$outputstack[\$outputstack_i] .= " . implode (" . ", $text_and_var_buffer) . ";\n"; + $text_and_var_buffer = array(); + } + if(isset(self::$builtins[$node->name])) { + /* PHP's parser fails once again... Apparently we cannot call a function from an array that is a static property */ + $func = self::$builtins[$node->name]; + $code .= $func($node); + } else { + $paramarray = self::tempvar("parameters"); + $code .= "\$$paramarray = array();\n"; + + foreach($node->params as $pname => $pcontent) { + list($pval, $pre) = self::_transcompile($pcontent, true); + $code .= $pre . "\$${paramarray}['" . Misc::escape_text($pname) . "'] = " . $pval . ";\n"; + } + + $code .= "\$outputstack[\$outputstack_i] .= \$ste->call_tag('" . Misc::escape_text($node->name) . "', \$${paramarray}, "; + $code .= empty($node->sub) ? "function(\$ste) { return ''; }" : ("\$ste->make_closure(" . self::transcompile($node->sub) . ")"); + $code .= ");\n"; + } + } + } + + if($avoid_outputstack && ($code == "")) { + return array(implode (" . ", $text_and_var_buffer), ""); + } + + if(!empty($text_and_var_buffer)) { + $code .= "\$outputstack[\$outputstack_i] .= ". implode (" . ", $text_and_var_buffer) . ";\n"; + } + + if($avoid_outputstack) { + $tmpvar = self::tempvar("tmp"); + $code = "\$outputstack[] = '';\n\$outputstack_i++;" . $code; + $code .= "\$$tmpvar = array_pop(\$outputstack);\n\$outputstack_i--;\n"; + return array("\$$tmpvar", $code); + } + + return $code; + } + + /* + * Function: transcompile + * Transcompiles an abstract syntax tree to PHP. + * You only need this function, if you want to manually transcompile a template. + * + * Parameters: + * $ast - The abstract syntax tree to transcompile. + * + * Returns: + * PHP code. The PHP code is an anonymous function expecting a <STECore> instance as its parameter and returns a string (everything that was not pached into a section). + */ + public static function transcompile($ast) { /* self::Transcompile and add some boilerplate code. */ + $boilerplate = "\$outputstack = array('');\n\$outputstack_i = 0;\n"; + return "function(\$ste)\n{\n" . self::indent_code($boilerplate . self::_transcompile($ast) . "return array_pop(\$outputstack);") . "\n}"; + } +} + +Transcompiler::init_builtins(); |