Path: | rdoc/en/parser.en.rdoc |
Last Update: | Wed Apr 17 05:46:19 +0000 2013 |
: do_parse -> Object
The entry point of parser. This method is used with #next_token. If Racc wants to get token (and its value), calls next_token. -- # Example ---- inner def parse @q = [[1,1], [2,2], [3,3], [false, '$']] do_parse end def next_token @q.shift end --
: next_token -> [Symbol, Object]
[abstract method] The method to fetch next token. If you use #do_parse method, you must implement #next_token. The format of return value is [TOKEN_SYMBOL, VALUE]. token-symbol is represented by Ruby's symbol by default, e.g. :IDENT for 'IDENT'. ";" (String) for ';'. The final symbol (End of file) must be false.
: yyparse( receiver, method_id )
The another entry point of parser. If you use this method, you must implement RECEIVER#METHOD_ID method. RECEIVER#METHOD_ID is a method to get next token. It must 'yield's token, which format is [TOKEN-SYMBOL, VALUE].
: on_error( error_token_id, error_value, value_stack )
This method is called when parse error is found. ERROR_TOKEN_ID is an internal ID of token which caused error. You can get string replesentation of this ID by calling #token_to_str. ERROR_VALUE is a value of error token. value_stack is a stack of symbol values. DO NOT MODIFY this object. This method raises ParseError by default. If this method returns, parsers enter "error recovering mode".
: token_to_str( t ) -> String
Convert internal ID of token symbol to the string.
: yyerror
Enter error recovering mode. This method does not call #on_error.
: yyerrok
Leave error recovering mode.
: yyaccept
Exit parser. Return value is Symbol_Value_Stack[0].