* array( * array( * 'class' => Class name of token, * 'match' => Regular expression to match, * ), * ... * ) * * * The array is evaluated in the given order, until one of the regular * expressions match. The regular expression should have at least one named * match (?P ... ), with the name "value", which will be assigned to the * token, created form the given class name, as its content. The matched * contents will be removed from the beginning of the string. * Optionally a second named match, called "match", may be used inside the * regular expression. If so, only the contents inside this match will be * removed from the beginning of the string. This enables you to perform a * trivial lookahead inside the tokenizer. * * If no expression matches, an exception will be thrown. * * Token filtering * --------------- * * After all tokens are extracted from the text, they may miss some values, * which may be required by the parser, like the level of title tokens. Those * should be extracted and assigned during the filtering stage. For this the * filterTokens() method should be implemented, which may iterate over the * token stream and assign the required values. * * If the wiki markup language supports plugins you may also want to "parse" * the plugin contents to extract type, parameters and its text here. * * @package Document * @version //autogen// */ abstract class ezcDocumentWikiTokenizer { /** * List with tokens and a regular expression matching the given token. * * The tokens are matched in the given order. * * @var array */ protected $tokens = array(); /** * Construct tokenizer * * Create token array with regular repression matching the respective * token. * * @return void */ abstract public function __construct(); /** * Tokenize the given file * * The method tries to tokenize the passed files and returns an array of * ezcDocumentWikiToken struct on succes, or throws a * ezcDocumentTokenizerException, if something could not be matched by any * token. * * @param string $file * @return array */ public function tokenizeFile( $file ) { if ( !file_exists( $file ) || !is_readable( $file ) ) { throw new ezcBaseFileNotFoundException( $file ); } return $this->tokenizeString( file_get_contents( $file ) ); } /** * Convert tabs to spaces * * Convert all tabs to spaces, as defined in: * http://docutils.sourceforge.net/docs/ref/rst/restructuredtext.html#whitespace * * @param ezcDocumentWikiToken $token * @return void */ protected function convertTabs( ezcDocumentWikiToken $token ) { while ( ( $position = strpos( $token->content, "\t" ) ) !== false ) { $token->content = substr( $token->content, 0, $position ) . str_repeat( ' ', 9 - ( ( $position + $token->position ) % 8 ) ) . substr( $token->content, $position + 1 ); } } /** * Filter tokens * * Method to filter tokens, after the input string ahs been tokenized. The * filter should extract additional information from tokens, which are not * generally available yet, like the depth of a title depending on the * title markup. * * @param array $tokens * @return array */ abstract protected function filterTokens( array $tokens ); /** * Tokenize the given string * * The method tries to tokenize the passed strings and returns an array of * ezcDocumentWikiToken struct on succes, or throws a * ezcDocumentTokenizerException, if something could not be matched by any * token. * * @param string $string * @return array */ public function tokenizeString( $string ) { $line = 0; $position = 1; $tokens = array(); $string = "\n" . $string; // Normalize newlines $string = preg_replace( '([\x20\\t]*(?:\\r\\n|\\r|\\n))', "\n", $string ); while ( strlen( $string ) > 0 ) { foreach ( $this->tokens as $match ) { if ( preg_match( $match['match'], $string, $matches ) ) { // If the first part of the match is a // newline, add a respective token to the // stack. if ( ( $matches[0][0] === "\n" ) && ( $match['class'] !== 'ezcDocumentWikiNewLineToken' ) ) { $tokens[] = new ezcDocumentWikiNewLineToken( $matches[0][0], $line, $position ); ++$line; $position = 0; } // A token matched, so add the matched token to the token // list and update all variables. $class = $match['class']; $newToken = new $class( ( isset( $matches['value'] ) ? $matches['value'] : null ), $line, $position ); $match = isset( $matches['match'] ) ? $matches['match'] : $matches[0]; // Removed matched stuff from input string $string = substr( $string, $length = strlen( $match ) ); // On a newline token reset the line position and increase the line value if ( $newToken instanceof ezcDocumentWikiNewLineToken ) { ++$line; $position = 0; } else { // Otherwise still update the line // value, when there is at minimum // one newline in the match. This may // lead to a false position value. if ( ( $newLines = substr_count( $match, "\n" ) ) > 0 ) { $line += $newLines; $position = 0; } } // Convert tabs to spaces for whitespace tokens if ( $newToken instanceof ezcDocumentWikiWhitespaceToken ) { $this->convertTabs( $newToken ); } // If we found an explicit EOF token, just exit the parsing process. if ( $newToken instanceof ezcDocumentWikiEndOfFileToken ) { break 2; } // Add token to extracted token list $tokens[] = $newToken; // Update position, not before converting tabs to spaces. $position += ( $newToken instanceof ezcDocumentWikiNewLineToken ) ? 1 : strlen( $newToken->content ); // Restart the while loop, because we matched a token and // can retry with shortened string. continue 2; } } // None of the token definitions matched the input string. We throw // an exception with the position of the content in the input // string and the contents we could not match. // // This should never been thrown, but it is hard to prove that // there is nothing which is not matched by the regualr expressions // above. throw new ezcDocumentWikiTokenizerException( $line, $position, $string ); } // Finally append ainother newline token and a end of file token, to // make parsing the end easier. $tokens[] = new ezcDocumentWikiNewLineToken( "\n", $line, $position ); $tokens[] = new ezcDocumentWikiNewLineToken( "\n", $line, $position ); $tokens[] = new ezcDocumentWikiEndOfFileToken( null, $line, $position ); return $this->filterTokens( $tokens ); } } ?>