Hello. I'm currently implementing a MicroJava compiler for a college assignment (the implemented language was defined, the implementation language was of free choice). I've sucessfully implemented the lexer using Parsec. It has the type String -> Parser [MJVal], where MJVal are all the possible tokens. However, I don't know how to implement the parser, or at least how to do it keeping it distinguished from the lexer. For example, the MicroJava grammar specifies: Program = "program" ident {ConstDecl | VarDecl | ClassDecl} "{" {MethodDecl} "}". The natural solution (for me) would be: program = do string "program" programName <- identifier ... However, I can't do this because the file is already tokenized, what I have is something like: [Program_, identifier_ "testProgram", lBrace_, ...] for the example program: program testProgram { ... How should I implement the parser separated from the lexer? That is, how should I parse Tokens instead of Strings in the "Haskell way"? Fernando Henrique Sanches