Renamed transform.php to stupid_template_engine.php

1 files changed, 996 insertions, 0 deletions

diff --git a/stupid_template_engine.php b/stupid_template_engine.php
new file mode 100644
index 0000000..bd6efea
--- /dev/null
+++ b/stupid_template_engine.php
@@ -0,0 +1,996 @@
+<?php
+
+namespace ste;
+
+class TextNode
+{
+	public $text;
+}
+
+class TagNode
+{
+	public $name;
+	public $params;
+	public $sub;
+}
+
+class VariableNode
+{
+	public $name;
+	public $arrayfields;
+	public function transcompile()
+	{
+		$varaccess = '@$ste->vars[' . (is_numeric($this->name) ? $this->name : '\'' . escape_text($this->name) . '\''). ']';
+		foreach($this->arrayfields as $af)
+		{
+			if((count($af) == 1) and ($af[0] instanceof TextNode) and is_numeric($af->text))
+				$varaccess .= '[' . $af->text . ']';
+			else
+				$varaccess .= '[' . implode(".",
+					array_map(
+						function($node)
+						{
+							if($node instanceof TextNode)
+								return "\"" . escape_text($node->text) . "\"";
+							else if($node instanceof VariableNode)
+								return $node->transcompile;
+						}, $af
+					)
+				). ']';
+		}
+		return $varaccess;
+	}
+}
+
+/* $text must start after the first opening bracket */
+function find_closing_bracket($text, $opening, $closing)
+{
+	$counter = 1;
+	$len = strlen($text);
+	for($i = 0; $i < $len; ++$i)
+	{
+		switch($text[$i])
+		{
+			case $opening:
+				++$counter;
+				break;
+			case $closing:
+				--$counter;
+				break;
+		}
+		if($counter == 0)
+			break;
+	}
+	
+	if($counter > 0)
+		throw new \Exception("Missing closing \"$closing\". Stop.");
+	
+	return $i;
+}
+
+function unescape_text($text)
+{
+	$text = preg_replace("/(?:(?<!\\\\)\\\\\\\$)/s", "$", $text);
+	return str_replace("\\\\", "\\", $text);
+}
+
+function tokenize_text($text)
+{
+	$tokens = array();
+	/* Find next non-escaped $-char */
+	if(preg_match("/(?:(?<!\\\\)\\$)/s", $text, $match, PREG_OFFSET_CAPTURE) == 0)
+	{
+		$node = new TextNode();
+		$node->text = unescape_text($text);
+		return (strlen($node->text) == 0) ? array() : array($node);
+	}
+	
+	if($match[0][1] > 0)
+	{
+		$node = new TextNode();
+		$node->text = unescape_text(substr($text, 0, $match[0][1]));
+		$tokens[] = $node;
+	}
+	
+	if($text[$match[0][1] + 1] == "{")
+	{
+		$varend = find_closing_bracket(substr($text, $match[0][1] + 2), "{", "}") + $match[0][1] + 2;
+		return array_merge(
+			$tokens,
+			tokenize_text("\$" . substr($text, $match[0][1] + 2, ($varend - 1) - ($match[0][1] + 1))),
+			tokenize_text(substr($text, $varend + 1))
+		);
+	}
+	
+	$text = substr($text, $match[0][1] + 1);
+	if(preg_match("/^[a-zA-Z0-9_]+/s", $text, $match, PREG_OFFSET_CAPTURE) == 0)
+	{
+		$nexttokens = tokenize_text($text);
+		if($nexttokens[0] instanceof Text)
+			$nexttokens[0]->text = "\$" . $nexttokens[0]->text;
+		else
+		{
+			$node = new TextNode();
+			$node->text = "\$";
+			$tokens[] = $node;
+		}
+		return array_merge($tokens, $nexttokens);
+	}
+	
+	$node = new VariableNode();
+	$node->name = $match[0][0];
+	$node->arrayfields = array();
+	
+	$text = substr($text, $match[0][1] + strlen($match[0][0]));
+	while(@$text[0] == "[")
+	{
+		$text = substr($text, 1);
+		$fieldend = find_closing_bracket($text, "[", "]");
+		$node->arrayfields[] = tokenize_text(substr($text, 0, $fieldend));
+		$text = substr($text, $fieldend + 1);
+	}
+	
+	$tokens[] = $node;
+	
+	return strlen($text) > 0 ? array_merge($tokens, tokenize_text($text)) : $tokens;
+}
+
+function mk_ast($code)
+{
+	$ast = array();
+	
+	if(preg_match("/\\<\\s*ste:([a-zA-Z0-9_]*)/s", $code, $matches, PREG_OFFSET_CAPTURE) == 0)
+		return tokenize_text($code);
+	
+	$ast = tokenize_text(substr($code, 0, $matches[0][1]));
+	
+	$tag = new TagNode();
+	$tag->name = $matches[1][0];
+	
+	$code = substr($code, $matches[0][1] + strlen($matches[0][0]));
+	
+	$tag->params = array();
+	
+	while(preg_match("/^\\s+([a-zA-Z0-9_]+)=((?:\"(?:.*?)(?<!\\\\)\")|(?:'(?:.*?)(?<!\\\\)'))/s", $code, $matches, PREG_OFFSET_CAPTURE) > 0)
+	{
+		$paramval = substr($code, $matches[2][1] + 1, strlen($matches[2][0]) - 2);
+		$paramval = str_replace("\\\"", "\"", $paramval);
+		$paramval = str_replace("\\'", "'", $paramval);
+		$tag->params[$matches[1][0]] = tokenize_text($paramval);
+		$code = substr($code, strlen($matches[0][0]));
+	}
+	
+	if(preg_match("/^\\s*([\\/]?)\\s*\\>/s", $code, $matches) == 0)
+		throw new \Exception("Missing closing '>' in \"" . $tag->name . "\"-Tag. Stop. (:::CODE START:::$code:::CODE END:::)");
+	
+	$code = substr($code, strlen($matches[0]));
+	
+	$tag->sub = array();
+	
+	if($matches[1][0] != "/")
+	{
+		$tags_open = 1;
+		$off = 0;
+		$last_tag_start = 0;
+		while(preg_match("/\\<((?:\\s*)|(?:\\s*\\/\\s*))ste:([a-zA-Z0-9_]*)(?:\\s+(?:[a-zA-Z0-9_]+)=(?:(?:\"(?:.*?)(?<!\\\\)\")|(?:'(?:.*?)(?<!\\\\)')))*((?:\\s*)|(?:\\s*\\/\\s*))\\>/s", $code, $matches, PREG_OFFSET_CAPTURE, $off) > 0) /* RegEx from hell! Matches all  <ste:> Tags. Opening, closing and self-closing ones. */
+		{
+			if(trim($matches[3][0]) != "/")
+			{
+				$closingtag = trim($matches[1][0]);
+				if($closingtag[0] == "/")
+					$tags_open--;
+				else
+					$tags_open++;
+			}
+			$last_tag_start = $matches[0][1];
+			$off = $last_tag_start + strlen($matches[0][0]);
+			if($tags_open == 0)
+				break;
+		}
+		
+		if(($tags_open != 0) or ($tag->name != $matches[2][0]))
+			throw new \Exception("Missing closing \"ste:" . $tag->name . "\"-Tag. Stop.");
+		
+		if($tag->name == "rawtext")
+		{
+			$tag = new TextNode();
+			$tag->text = substr($code, 0, $last_tag_start);
+		}
+		else
+			$tag->sub = mk_ast(substr($code, 0, $last_tag_start));
+		$code = substr($code, $off);
+	}
+	
+	$ast[] = $tag;
+	return array_merge($ast, strlen($code) > 0 ? mk_ast($code) : array());
+}
+
+function parse($code)
+{
+	/* Precompiling... */
+	$code = preg_replace("/\\<\\s*ste:comment\\s*\\>.*?\\<\\s*\\/\\s*ste:comment\\s*\\>/s", "", $code); /* Remove comments */
+	$code = preg_replace( /* Transform short form of if-clause (?{cond|then|else}) to long form */
+		"/(?:(?<!\\\\)\\?)(?:(?<!\\\\)\\{)(.*?)(?:(?<!\\\\)\\|)(.*?)(?:(?<!\\\\)\\|)(.*?)(?:(?<!\\\\)\\})/s",
+		"<ste:if>\$1<ste:then>\$2</ste:then><ste:else>\$3</ste:else></ste:if>",
+		$code
+	);
+	/* Unescape \? \{ \} \| */
+	$code = preg_replace("/(?:(?<!\\\\)\\\\\\?)/s", "?", $code);
+	$code = preg_replace("/(?:(?<!\\\\)\\\\\\{)/s", "{", $code);
+	$code = preg_replace("/(?:(?<!\\\\)\\\\\\})/s", "}", $code);
+	$code = preg_replace("/(?:(?<!\\\\)\\\\\\|)/s", "|", $code);
+	
+	/* Create abstract syntax tree */
+	return mk_ast($code);
+}
+
+define("MODE_SOURCE", 0);
+define("MODE_TRANSCOMPILED", 1);
+
+interface StorageAccess
+{
+	public function load($tpl, &$mode);
+	public function save($tpl, $data, $mode);
+}
+
+class FilesystemStorageAccess implements StorageAccess
+{
+	protected $sourcedir;
+	protected $transcompileddir;
+	
+	public function __construct($src, $transc)
+	{
+		$this->sourcedir        = $src;
+		$this->transcompileddir = $transc;
+	}
+	
+	public function load($tpl, &$mode)
+	{
+		$src_fn    = $this->sourcedir        . "/" . $tpl;
+		$transc_fn = $this->transcompileddir . "/" . $tpl . ".php";
+		
+		if($mode == MODE_SOURCE)
+		{
+			$content = @file_get_contents($src_fn);
+			if($content === False)
+				throw new \Exception("Template not found.");
+			return $content;
+		}
+		
+		$src_stat    = @stat($src_fn);
+		$transc_stat = @stat($transc_fn);
+		
+		if(($src_stat === False) and ($transc_stat === False))
+			throw new \Exception("Template not found.");
+		else if($transc_stat === False)
+		{
+			$mode = MODE_SOURCE;
+			return file_get_contents($src_fn);
+		}
+		else if($src_stat === False)
+		{
+			include($transc_fn);
+			return $transcompile_fx;
+		}
+		else
+		{
+			if($src_stat["mtime"] > $transc_stat["mtime"])
+			{
+				$mode = MODE_SOURCE;
+				return file_get_contents($src_fn);
+			}
+			else
+			{
+				include($transc_fn);
+				return $transcompile_fx;
+			}
+		}
+	}
+	
+	public function save($tpl, $data, $mode)
+	{
+		$fn = (($mode == MODE_SOURCE) ? $this->sourcedir : $this->transcompileddir) . "/" . $tpl . (($mode == MODE_TRANSCOMPILED) ? ".php" : "");
+		@mkdir(dirname($fn), 0777, True);
+		file_put_contents($fn, "<?php \$transcompile_fx = $data; ?>");
+		chmod($fn, 0777); /* FIXME: Remove this line after debugging... */
+	}
+}
+
+function indent_code($code)
+{
+	return implode(
+		"\n",
+		array_map(
+			function($line) { return "\t$line"; },
+			explode("\n", $code)
+		)
+	);
+}
+
+/* We could also just eval() the $infix_math code, but this is much cooler :-D (Parser inception) */
+function shunting_yard($infix_math)
+{
+	$operators = array(
+		"+" => array("l", 2),
+		"-" => array("l", 2),
+		"*" => array("l", 3),
+		"/" => array("l", 3),
+		"^" => array("r", 4),
+		"_" => array("r", 5),
+		"(" => array("", 0), 
+		")" => array("", 0)
+	);
+	
+	preg_match_all("/\s*(?:(?:[+\\-\\*\\/\\^\\(\\)])|(\\d*[\\.]?\\d*))\\s*/s", $infix_math, $tokens, PREG_PATTERN_ORDER);
+	$tokens_raw = array_filter(array_map('trim', $tokens[0]), function($x) { return ($x === "0") or (!empty($x)); });
+	$output_queue = array();
+	$op_stack     = array();
+	
+	$lastpriority = NULL;
+	/* Make - unary, if neccessary */
+	$tokens = array();
+	foreach($tokens_raw as $token)
+	{
+		$priority = isset($operators[$token]) ? $operators[$token][1] : -1;
+		if(($token == "-") and (($lastpriority === NULL) or ($lastpriority >= 0)))
+		{
+			$priority = $operators["_"][1];
+			$tokens[] = "_";
+		}
+		else
+			$tokens[] = $token;
+		$lastpriority = $priority;
+	}
+	
+	while(!empty($tokens))
+	{
+		$token = array_shift($tokens);
+		if(is_numeric($token))
+			$output_queue[] = $token;
+		else if($token == "(")
+			$op_stack[] = $token;
+		else if($token == ")")
+		{
+			$lbr_found = False;
+			while(!empty($op_stack))
+			{
+				$op = array_pop($op_stack);
+				if($op == "(")
+				{
+					$lbr_found = True;
+					break;
+				}
+				$output_queue[] = $op;
+			}
+			if(!$lbr_found)
+				throw new \Exception("Bracket mismatch.");
+		}
+		else if(!isset($operators[$token]))
+			throw new \Exception("Invalid token ($token): Not a number, bracket or operator. Stop.");
+		else
+		{
+			$priority = $operators[$token][1];
+			if($operators[$token][0] == "l")
+				while((!empty($op_stack)) and ($priority <= $operators[$op_stack[count($op_stack)-1]][1]))
+					$output_queue[] = array_pop($op_stack);
+			else
+				while((!empty($op_stack)) and ($priority < $operators[$op_stack[count($op_stack)-1]][1]))
+					$output_queue[] = array_pop($op_stack);
+			$op_stack[] = $token;
+		}
+	}
+	
+	while(!empty($op_stack))
+	{
+		$op = array_pop($op_stack);
+		if($op == "(")
+			throw new \Exception("Bracket mismatch...");
+		$output_queue[] = $op;
+	}
+	
+	return $output_queue;
+}
+
+function pop2(&$array)
+{
+	$rv = array(array_pop($array), array_pop($array));
+	if(array_search(NULL, $rv, True) !== False)
+		throw new \Exception("Not enough numbers on stack. Invalid formula.");
+	return $rv;
+}
+
+function calc_rpn($rpn)
+{
+	$stack = array();
+	foreach($rpn as $token)
+	{
+		switch($token)
+		{
+			case "+":
+				list($b, $a) = pop2($stack);
+				$stack[] = $a + $b;
+				break;
+			case "-":
+				list($b, $a) = pop2($stack);
+				$stack[] = $a - $b;
+				break;
+			case "*":
+				list($b, $a) = pop2($stack);
+				$stack[] = $a * $b;
+				break;
+			case "/":
+				list($b, $a) = pop2($stack);
+				$stack[] = $a / $b;
+				break;
+			case "^":
+				list($b, $a) = pop2($stack);
+				$stack[] = pow($a, $b);
+				break;
+			case "_":
+				$a = array_pop($stack);
+				if($a === NULL)
+					throw new \Exception("Not enough numbers on stack. Invalid formula.");
+				$stack[] = -$a;
+				break;
+			default:
+				$stack[] = $token;
+				break;
+		}
+	}
+	return array_pop($stack);
+}
+
+function loopbody($code)
+{
+	return "try\n{\n" . indent_code($code) . "\n}\ncatch(\ste\BreakException \$e) { break; }\ncatch(\ste\ContinueException \$e) { continue; }\n";
+}
+
+$ste_builtins = array(
+	"if" => function($ast)
+	{
+		$output = "";
+		$condition = array();
+		$then = array();
+		$else = array();
+		
+		foreach($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[] = $node;
+		}
+		
+		if(empty($then))
+			throw new \Exception("Transcompile error: Missing <ste:else> in <ste:if>. Stop.");
+		
+		$output .= "\$outputstack[] = \"\";\n\$outputstack_i++;\n";
+		$output .= _transcompile($condition);
+		$output .= "\$outputstack_i--;\nif(\$ste->evalbool(array_pop(\$outputstack)))\n{\n";
+		$output .= indent_code(_transcompile($then));
+		$output .= "\n}\n";
+		if(!empty($else))
+		{
+			$output .= "else\n{\n";
+			$output .= indent_code(_transcompile($else));
+			$output .= "\n}\n";
+		}
+		return $output;
+	},
+	"cmp" => function($ast)
+	{
+		$code = "";
+		
+		$code .= "\$outputstack[] = '';\n\$outputstack_i++;\n";
+		if(isset($ast->params["var_b"]))
+		{
+			$code .= _transcompile($ast->params["var_b"]);
+			$b = '$ste->get_var_by_name(array_pop($outputstack))';
+		}
+		else if(isset($ast->params["text_b"]))
+		{
+			$code .= _transcompile($ast->params["text_b"]);
+			$b = 'array_pop($outputstack)';
+		}
+		else
+			throw new \Exception("Transcompile error: neiter var_b nor text_b set in <ste:cmp>. Stop.");
+		
+		$code .= "\$outputstack[] = '';\n\$outputstack_i++;\n";
+		if(isset($ast->params["var_a"]))
+		{
+			$code .= _transcompile($ast->params["var_a"]);
+			$a = '$ste->get_var_by_name(array_pop($outputstack))';
+		}
+		else if(isset($ast->params["text_a"]))
+		{
+			$code .= _transcompile($ast->params["text_a"]);
+			$a = 'array_pop($outputstack)';
+		}
+		else
+			throw new \Exception("Transcompile error: neiter var_a nor text_a set in <ste:cmp>. Stop.");
+		
+		$code .= "\$outputstack[] = '';\n\$outputstack_i++;\n";
+		if(isset($ast->params["op"]))
+			$code .= _transcompile($ast->params["op"]);
+		else
+			throw new \Exception("Transcompile error: op not given in <ste:cmp>. Stop.");
+		
+		$code .= "\$outputstack_i -= 3;\nswitch(trim(array_pop(\$outputstack)))\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";
+				},
+				array(
+					array('eq', '=='),
+					array('neq', '!='),
+					array('lt', '<'),
+					array('lte', '<='),
+					array('gt', '>'),
+					array('gte', '>=')
+				)
+			));
+		$code .= "default: throw new \Exception('Runtime Error: Unknown operator in <ste:cmp>.');\n}\n";
+		return $code;
+	},
+	"not" => function($ast)
+	{
+		$code = "\$outputstack[] = '';\n\$outputstack_i++;\n";
+		$code .= _transcompile($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";
+		$code .= _transcompile($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 = "";
+		$loopname = "forloop_" . str_replace(".", "_", uniqid("",True));
+		if(empty($ast->params["start"]))
+			throw new \Exception("Transcompile error: Missing 'start' parameter in <ste:for>. Stop.");
+		$code .= "\$outputstack[] = '';\n\$outputstack_i++;\n";
+		$code .= _transcompile($ast->params["start"]);
+		$code .= "\$outputstack_i--;\n\$${loopname}_start = array_pop(\$outputstack);\n";
+		
+		if(empty($ast->params["stop"]))
+			throw new \Exception("Transcompile error: Missing 'end' parameter in <ste:for>. Stop.");
+		$code .= "\$outputstack[] = '';\n\$outputstack_i++;\n";
+		$code .= _transcompile($ast->params["stop"]);
+		$code .= "\$outputstack_i--;\n\$${loopname}_stop = array_pop(\$outputstack);\n";
+		
+		if(empty($ast->params["step"]))
+			$code .= "\$${loopname}_step = 1;\n";
+		else
+		{
+			$code .= "\$outputstack[] = '';\n\$outputstack_i++;\n";
+			$code .= _transcompile($ast->params["step"]);
+			$code .= "\$outputstack_i--;\n\$${loopname}_step = array_pop(\$outputstack);\n";
+		}
+		
+		if(!empty($ast->params["counter"]))
+		{
+			$code .= "\$outputstack[] = '';\n\$outputstack_i++;\n";
+			$code .= _transcompile($ast->params["counter"]);
+			$code .= "\$outputstack_i--;\n\$${loopname}_countername = array_pop(\$outputstack);\n";
+		}
+		
+		$loopbody = empty($ast->params["counter"]) ? "" : "\$ste->set_var_by_name(\$${loopname}_countername, \$${loopname}_counter);\n";
+		$loopbody .= _transcompile($ast->sub);
+		$loopbody = indent_code("{\n" . loopbody(indent_code($loopbody)) . "\n}\n");
+		
+		$code .= "if(\$${loopname}_step == 0)\n\tthrow new \Exception('Runtime Error: step can not be 0 in <ste:for>. Stop.');\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";
+		
+		return $code;
+	},
+	"foreach" => function($ast)
+	{
+		$loopname = "foreachloop_" . str_replace(".", "_", uniqid("",True));
+		$code = "";
+		
+		if(empty($ast->params["array"]))
+			throw new \Exception("Transcompile Error: array not givein in <ste:foreach>. Stop.");
+		$code .= "\$outputstack[] = '';\n\$outputstack_i++;\n";
+		$code .= _transcompile($ast->params["array"]);
+		$code .= "\$outputstack_i--;\n\$${loopname}_arrayvar = array_pop(\$outputstack);\n";
+		
+		if(empty($ast->params["value"]))
+			throw new \Exception("Transcompile Error: value not givein in <ste:foreach>. Stop.");
+		$code .= "\$outputstack[] = '';\n\$outputstack_i++;\n";
+		$code .= _transcompile($ast->params["value"]);
+		$code .= "\$outputstack_i--;\n\$${loopname}_valuevar = array_pop(\$outputstack);\n";
+		
+		if(!empty($ast->params["key"]))
+		{
+			$code .= "\$outputstack[] = '';\n\$outputstack_i++;\n";
+			$code .= _transcompile($ast->params["key"]);
+			$code .= "\$outputstack_i--;\n\$${loopname}_keyvar = array_pop(\$outputstack);\n";
+		}
+		
+		if(!empty($ast->params["counter"]))
+		{
+			$code .= "\$outputstack[] = '';\n\$outputstack_i++;\n";
+			$code .= _transcompile($ast->params["counter"]);
+			$code .= "\$outputstack_i--;\n\$${loopname}_countervar = array_pop(\$outputstack);\n";
+		}
+		
+		$code .= "\$${loopname}_array = \$ste->get_var_by_name(\$${loopname}_arrayvar);\n";
+		$code .= "if(!is_array(\$${loopname}_array))\n\t\$${loopname}_array = array();\n";
+		$code .= "\$${loopname}_counter = 0;\n";
+		
+		$loopbody = "\$${loopname}_counter++;\n\$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";
+		if(!empty($ast->params["counter"]))
+			$loopbody .= "\$ste->set_var_by_name(\$${loopname}_countervar, \$${loopname}_counter);\n";
+		$loopbody .= "\n";
+		$loopbody .= _transcompile($ast->sub);
+		$loopbody = "{\n" . loopbody(indent_code($loopbody)) . "\n}\n";
+		
+		$code .= "foreach(\$${loopname}_array as \$${loopname}_key => \$${loopname}_value)\n$loopbody\n";
+		
+		return $code;
+	},
+	"infloop" => function($ast)
+	{
+		return "while(True)\n{\n" . loopbody(indent_code(_transcompile($ast->sub)) . "\n}") . "\n";
+	},
+	"break" => function($ast)
+	{
+		return "\$ste->break_loop();\n";
+	},
+	"continue" => function($ast)
+	{
+		return "\$ste->continue_loop();\n";
+	},
+	"block" => function($ast)
+	{
+		if(empty($ast->name))
+			throw new \Exception("Transcompile Error: name missing in <ste:block>. Stop.");
+		
+		$blknamevar = "blockname_" . str_replace(".", "_", uniqid("", True));
+		
+		$code = "\$outputstack[] = '';\n\$outputstack_i++;\n";
+		$code .= _transcompile($ast->params["name"]);
+		$code .= "\$outputstack_i--;\n\$${blknamevar} = array_pop(\$outputstack);\n";
+		
+		$tmpblk = uniqid("", True);
+		$code .= "\$ste->blocks['$tmpblk'] = array_pop(\$outputstack);\n\$ste->blockorder[] = '$tmpblk';\n\$outputstack = array('');\n\$outputstack_i = 0;\n";
+		
+		$code .= _transcompile($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 \Exception("Transcompile Error: name missing in <ste:load>. Stop.");
+		
+		$code = "\$outputstack[] = '';\n\$outputstack_i++;\n";
+		$code .= _transcompile($ast->params["name"]);
+		$code .= "\$outputstack_i--;\n\$outputstack[\$outputstack_i] .= \$ste->load(array_pop(\$outputstack));\n";
+		
+		return $code;
+	},
+	"mktag" => function($ast)
+	{
+		if(empty($ast->params["name"]))
+			throw new \Exception("Transcompile Error: name missing in <ste:mktag>. Stop.");
+		
+		$code = "\$outputstack[] = '';\n\$outputstack_i++;\n";
+		$code .= _transcompile($ast->params["name"]);
+		$code .= "\$outputstack_i--;\n\$tagname = array_pop(\$outputstack);\n";
+		
+		$fxbody = "\$outputstack = array(); \$outputstack_i = 0;\$ste->vars['_tag_parameters'] = \$params;\n";
+		
+		if(!empty($ast->params["mandatory"]))
+		{
+			$code .= "\$outputstack[] = '';\n\$outputstack_i++;\n";
+			$code .= _transcompile($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 \Exception(\"Runtime Error: \$mp missing in <ste:\$tagname>. Stop.\");\n}";
+		}
+		
+		$fxbody .= _transcompile($ast->sub);
+		$fxbody .= "return array_pop(\$outputstack);";
+		
+		$code .= "\$tag_fx = function(\$ste, \$params, \$sub) use (\$tagname, \$mandatory_params)\n{\n" . indent_code($fxbody) . "\n};\n";
+		$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 \Exception("Transcompile Error: var missing in <ste:set>. Stop.");
+		
+		$code = "\$outputstack[] = '';\n\$outputstack_i++;\n";
+		$code .= _transcompile($ast->params["var"]);
+		
+		$code .= "\$outputstack[] = '';\n\$outputstack_i++;\n";
+		$code .= _transcompile($ast->sub);
+		
+		$code .= "\$outputstack_i -= 2;\n\$newvartext = array_pop(\$outputstack);\n\$varname = array_pop(\$outputstack);\n";
+		$code .= "\$ste->set_var_by_name(\$varname, \$newvartext);\n";
+		
+		return $code;
+	},
+	"calc" => function($ast)
+	{
+		$code = "\$outputstack[] = '';\n\$outputstack_i++;\n";
+		$code .= _transcompile($ast->sub);
+		$code .= "\$outputstack_i--;\n\$outputstack[\$outputstack_i] .= \$ste->calc(array_pop(\$outputstack));\n";
+		
+		return $code;
+	}
+);
+
+function escape_text($text)
+{
+	return addcslashes($text, "\r\n\t\$\0..\x1f\\'\x7f..\xff");
+}
+
+function _transcompile($ast) /* The real transcompile function, does not add boilerplate code. */
+{
+	$code = "";
+	global $ste_builtins;
+	
+	foreach($ast as $node)
+	{
+		if($node instanceof TextNode)
+			$code .= "\$outputstack[\$outputstack_i] .= \"" . escape_text($node->text) . "\";\n";
+		else if($node instanceof VariableNode)
+			$code .= "\$outputstack[\$outputstack_i] .= " . $node->transcompile() . ";\n";
+		else if($node instanceof TagNode)
+		{
+			if(isset($ste_builtins[$node->name]))
+				$code .= $ste_builtins[$node->name]($node);
+			else
+			{
+				$paramarray = "parameters_" . str_replace(".", "_", uniqid("", True));
+				$code .= "\$$paramarray = array();\n";
+				
+				foreach($node->params as $pname => $pcontent)
+				{
+					$code .= "\$outputstack[] = '';\n\$outputstack_i++;\n";
+					$code .= _transcompile($pcontent);
+					$code .= "\$outputstack_i--;\n\$${paramarray}['" . escape_text($pname) . "'] = array_pop(\$outputstack);\n";
+				}
+				
+				$code .= "\$outputstack[\$outputstack_i] .= \$ste->call_tag('" . escape_text($node->name) . "', \$${paramarray}, " . transcompile($node->sub) . ");\n";
+			}
+		}
+	}
+	
+	return $code;
+}
+
+$ste_transc_boilerplate = "\$outputstack = array('');\n\$outputstack_i = 0;\n";
+
+function transcompile($ast) /* Transcompile and add some boilerplate code. */
+{
+	global $ste_transc_boilerplate;
+	return "function(\$ste)\n{\n" . indent_code($ste_transc_boilerplate . _transcompile($ast) . "return array_pop(\$outputstack);") . "\n}";
+}
+
+class BreakException    extends \Exception { }
+class ContinueException extends \Exception { }
+
+class STECore
+{
+	private $tags;
+	private $storage_access;
+	private $cur_tpl_dir;
+	public $blocks;
+	public $blockorder;
+	public $vars;
+	
+	public function __construct($storage_access)
+	{
+		$this->storage_access = $storage_access;
+		$this->cur_tpl_dir = "/";
+		STEStandardLibrary::_register_lib($this);
+		$this->vars = array();
+		$this->blockorder = array();
+		$this->blocks = array();
+	}
+	
+	public function register_tag($name, $callback)
+	{
+		if(!is_callable($callback))
+			throw new \Exception("Can not register tag \"$name\", not callable.");
+		if(empty($name))
+			throw new \Exception("Can not register tag, empty name.");
+		$this->tags[$name] = $callback;
+	}
+	
+	public function call_tag($name, $params, $sub)
+	{
+		if(!isset($this->tags[$name]))
+			throw new \Exception("Can not call tag \"$name\": Does not exist.");
+		return call_user_func($this->tags[$name], $this, $params, $sub);
+	}
+	
+	public function break_loop()
+	{
+		throw new BreakException();
+	}
+	
+	public function continue_loop()
+	{
+		throw new ContinueException();
+	}
+	
+	public function calc($expression)
+	{
+		return calc_rpn(shunting_yard($expression));
+	}
+	
+	public function exectemplate($tpl)
+	{
+		$output = "";
+		$lastblock = $this->load($tpl);
+		
+		foreach($this->blockorder as $blockname)
+			$output .= $this->blocks[$blockname];
+		
+		return $output . $lastblock;
+	}
+	
+	private function &get_var_reference(&$from, $name, $create_if_not_exist)
+	{
+		$bracket_open = strpos($name, "[");
+		if($bracket_open === False)
+		{
+			if(isset($from[$name]) or $create_if_not_exist)
+			{
+				$ref = &$from[$name];
+				return $ref;
+			}
+			else
+				return NULL;
+		}
+		else
+		{
+			$old_varname = $varname;
+			$bracket_close = strpos($name, "]", $bracket_open);
+			if($bracket_close === FALSE)
+				throw new Excpeption("Runtime Error: Invalid varname \"$varname\". Missing closing \"]\".");
+			$varname = substr($name, 0, $bracket_open);
+			$name    = substr($name, $bracket_open + 1, $bracket_close - $bracket_open - 1) . substr($name, $bracket_close + 1);
+			if(!is_array($from[$varname]))
+			{
+				if($create_if_not_exist)
+					$from[$varname] = array();
+				else
+					return NULL;
+			}
+			try
+			{
+				$ref = &$self->get_var_reference($from[$varname], $name, $create_if_not_exist);
+				return $ref;
+			}
+			catch(Exception $e)
+			{
+				throw new Excpeption("Runtime Error: Invalid varname \"$old_varname\". Missing closing \"]\".");
+			}
+		}
+	}
+	
+	public function set_var_by_name($name, $val)
+	{
+		$ref = &$this->get_var_reference($this->vars, $name, True);
+		$ref = $val;
+	}
+	
+	public function get_var_by_name($name)
+	{
+		$ref = $this->get_var_reference($this->vars, $name, False);
+		return $ref === NULL ? "" : $ref;
+	}
+	
+	public function load($tpl, $quiet=False)
+	{
+		$tpldir_b4 = $this->cur_tpl_dir;
+		
+		/* Resolve ".", ".." and protect from possible LFI */
+		$tpl = str_replace("\\", "/", $tpl);
+		if($tpl[0] != "/")
+			$tpl = $this->cur_tpl_dir . "/" . $tpl;
+		$pathex = array_filter(array_slice(explode("/", $tpl), 1), function($s) { return ($s != ".") and (!empty($s)); });
+		$pathex = array_merge($pathex);
+		while(($i = array_search("..", $pathex)) !== False)
+		{
+			if($i == 0)
+				$pathex = array_slice($pathex, 1);
+			else
+				$pathex = array_merge(array_slice($pathex, 0, $i), array_slice($pathex, $i + 2));
+		}
+		$tpl = implode("/", $pathex);
+		
+		if($quiet)
+		{
+			$blocks_back     = clone $this->blocks;
+			$blockorder_back = clone $this->blockorder;
+		}
+		
+		$mode = MODE_TRANSCOMPILED;
+		$content = $this->storage_access->load($tpl, $mode);
+		if($mode == MODE_SOURCE)
+		{
+			$ast    = parse($content);
+			$transc = transcompile($ast);
+			$this->storage_access->save($tpl, $transc, MODE_TRANSCOMPILED);
+			eval("\$content = $transc;");
+		}
+		
+		$output = $content($this);
+		
+		$this->cur_tpl_dir = $tpldir_b4;
+		
+		if($quiet)
+		{
+			$this->blocks     = $blocks_back;
+			$this->blockorder = $blockorder_back;
+		}
+		else
+			return $output;
+	}
+	
+	public function evalbool($txt)
+	{
+		return trim($txt) != "";
+	}
+}
+
+class STEStandardLibrary
+{
+	static public function _register_lib($ste)
+	{
+		foreach(get_class_methods(__CLASS__) as $method)
+			if($method[0] != "_")
+				$ste->register_tag($method, array(__CLASS__, $method));
+	}
+	
+	static public function escape($ste, $params, $sub)
+	{
+		return htmlentities($sub($ste), ENT_QUOTES, "UTF-8");
+	}
+	
+	static public function strlen($ste, $params, $sub)
+	{
+		return strlen($sub($ste));
+	}
+	
+	static public function array_len($ste, $params, $sub)
+	{
+		if(empty($params["var"]))
+			throw new \Exception("Runtime Error: missing var parameter in <ste:array_len>.");
+		$a = $ste->get_var_by_name($params["var"]);
+		return (is_array($a)) ? count($a) : "";
+	}
+}
+
+?>