Ada library for creating grammar parsers and lexers. Supports not only 8 bit streams but also Unicode and even streams of arbitrary objects. Powerful, flexible and extensible. Creates syntax tree. Has all standard parser constructs (alternatives, optional element etc.) and various pre-defined more complex constructs (e.g. different kinds of repetition). These constructs have even variations for subtly different needs (e.g. for different representation of data to be extracted). Arbitrary reliable look-ahead. No distinction between parser and lexer. Object oriented. Documented.