102 lines
		
	
	
		
			4.1 KiB
		
	
	
	
		
			PHP
		
	
	
		
		
			
		
	
	
			102 lines
		
	
	
		
			4.1 KiB
		
	
	
	
		
			PHP
		
	
	
|  | <?php | ||
|  | 
 | ||
|  | /* | ||
|  |  * This file is part of the Symfony package. | ||
|  |  * | ||
|  |  * (c) Fabien Potencier <fabien@symfony.com> | ||
|  |  * | ||
|  |  * For the full copyright and license information, please view the LICENSE | ||
|  |  * file that was distributed with this source code. | ||
|  |  */ | ||
|  | 
 | ||
|  | namespace Symfony\Component\ExpressionLanguage; | ||
|  | 
 | ||
|  | /** | ||
|  |  * Lexes an expression. | ||
|  |  * | ||
|  |  * @author Fabien Potencier <fabien@symfony.com> | ||
|  |  */ | ||
|  | class Lexer | ||
|  | { | ||
|  |     /** | ||
|  |      * Tokenizes an expression. | ||
|  |      * | ||
|  |      * @return TokenStream A token stream instance | ||
|  |      * | ||
|  |      * @throws SyntaxError | ||
|  |      */ | ||
|  |     public function tokenize(string $expression) | ||
|  |     { | ||
|  |         $expression = str_replace(["\r", "\n", "\t", "\v", "\f"], ' ', $expression); | ||
|  |         $cursor = 0; | ||
|  |         $tokens = []; | ||
|  |         $brackets = []; | ||
|  |         $end = \strlen($expression); | ||
|  | 
 | ||
|  |         while ($cursor < $end) { | ||
|  |             if (' ' == $expression[$cursor]) { | ||
|  |                 ++$cursor; | ||
|  | 
 | ||
|  |                 continue; | ||
|  |             } | ||
|  | 
 | ||
|  |             if (preg_match('/[0-9]+(?:\.[0-9]+)?([Ee][\+\-][0-9]+)?/A', $expression, $match, 0, $cursor)) { | ||
|  |                 // numbers
 | ||
|  |                 $number = (float) $match[0];  // floats
 | ||
|  |                 if (preg_match('/^[0-9]+$/', $match[0]) && $number <= \PHP_INT_MAX) { | ||
|  |                     $number = (int) $match[0]; // integers lower than the maximum
 | ||
|  |                 } | ||
|  |                 $tokens[] = new Token(Token::NUMBER_TYPE, $number, $cursor + 1); | ||
|  |                 $cursor += \strlen($match[0]); | ||
|  |             } elseif (str_contains('([{', $expression[$cursor])) { | ||
|  |                 // opening bracket
 | ||
|  |                 $brackets[] = [$expression[$cursor], $cursor]; | ||
|  | 
 | ||
|  |                 $tokens[] = new Token(Token::PUNCTUATION_TYPE, $expression[$cursor], $cursor + 1); | ||
|  |                 ++$cursor; | ||
|  |             } elseif (str_contains(')]}', $expression[$cursor])) { | ||
|  |                 // closing bracket
 | ||
|  |                 if (empty($brackets)) { | ||
|  |                     throw new SyntaxError(sprintf('Unexpected "%s".', $expression[$cursor]), $cursor, $expression); | ||
|  |                 } | ||
|  | 
 | ||
|  |                 [$expect, $cur] = array_pop($brackets); | ||
|  |                 if ($expression[$cursor] != strtr($expect, '([{', ')]}')) { | ||
|  |                     throw new SyntaxError(sprintf('Unclosed "%s".', $expect), $cur, $expression); | ||
|  |                 } | ||
|  | 
 | ||
|  |                 $tokens[] = new Token(Token::PUNCTUATION_TYPE, $expression[$cursor], $cursor + 1); | ||
|  |                 ++$cursor; | ||
|  |             } elseif (preg_match('/"([^"\\\\]*(?:\\\\.[^"\\\\]*)*)"|\'([^\'\\\\]*(?:\\\\.[^\'\\\\]*)*)\'/As', $expression, $match, 0, $cursor)) { | ||
|  |                 // strings
 | ||
|  |                 $tokens[] = new Token(Token::STRING_TYPE, stripcslashes(substr($match[0], 1, -1)), $cursor + 1); | ||
|  |                 $cursor += \strlen($match[0]); | ||
|  |             } elseif (preg_match('/(?<=^|[\s(])not in(?=[\s(])|\!\=\=|(?<=^|[\s(])not(?=[\s(])|(?<=^|[\s(])and(?=[\s(])|\=\=\=|\>\=|(?<=^|[\s(])or(?=[\s(])|\<\=|\*\*|\.\.|(?<=^|[\s(])in(?=[\s(])|&&|\|\||(?<=^|[\s(])matches|\=\=|\!\=|\*|~|%|\/|\>|\||\!|\^|&|\+|\<|\-/A', $expression, $match, 0, $cursor)) { | ||
|  |                 // operators
 | ||
|  |                 $tokens[] = new Token(Token::OPERATOR_TYPE, $match[0], $cursor + 1); | ||
|  |                 $cursor += \strlen($match[0]); | ||
|  |             } elseif (str_contains('.,?:', $expression[$cursor])) { | ||
|  |                 // punctuation
 | ||
|  |                 $tokens[] = new Token(Token::PUNCTUATION_TYPE, $expression[$cursor], $cursor + 1); | ||
|  |                 ++$cursor; | ||
|  |             } elseif (preg_match('/[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*/A', $expression, $match, 0, $cursor)) { | ||
|  |                 // names
 | ||
|  |                 $tokens[] = new Token(Token::NAME_TYPE, $match[0], $cursor + 1); | ||
|  |                 $cursor += \strlen($match[0]); | ||
|  |             } else { | ||
|  |                 // unlexable
 | ||
|  |                 throw new SyntaxError(sprintf('Unexpected character "%s".', $expression[$cursor]), $cursor, $expression); | ||
|  |             } | ||
|  |         } | ||
|  | 
 | ||
|  |         $tokens[] = new Token(Token::EOF_TYPE, null, $cursor + 1); | ||
|  | 
 | ||
|  |         if (!empty($brackets)) { | ||
|  |             [$expect, $cur] = array_pop($brackets); | ||
|  |             throw new SyntaxError(sprintf('Unclosed "%s".', $expect), $cur, $expression); | ||
|  |         } | ||
|  | 
 | ||
|  |         return new TokenStream($tokens, $expression); | ||
|  |     } | ||
|  | } |