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
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.
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].
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".
Convert internal ID of token symbol to the string.
Enter error recovering mode. This method does not call #on_error.
Leave error recovering mode.
Exit parser. Return value is Symbol_Value_Stack.