lexer class IDENTIFIER; lexer class KEYWORD dominates IDENTIFIER; lexer class IDENTIFIER submits to KEYWORD, BUILTIN; lexer class KEYWORD dominates Id_t;
Lexer classes are a useful tool in resolving lexical conflicts. If one DFA state can accept multiple valid tokens, it is normally an error during the lexical generator. However, if there is a lexer class relationship between those token, the token that dominates all others is selected instead as the resolution.
Lexer classes are declared as follows:
dominates lexer class or terminal list
to lexer class or terminal list
where both the dominates and submits lists are optional.