Efficient parsing with parser combinators.

Parser combinators offer a universal and flexible approach to parsing. They follow the structure of an underlying grammar, are modular, well-structured, easy to maintain, and can recognize a large variety of languages including context-sensitive ones. However, these advantages introduce a noticeable performance overhead mainly because the same powerful parsing algorithm is used to recognize even simple languages. Time-wise, parser combinators cannot compete with parsers generated by well-performing parser generators or optimized hand-written code.