Parsing is a package the provides a framework for building parsers. It introduces Parser, a type of function that parses a sequence of tokens, and Analyzer, a type of function that accepts input for the parser in its original form and separates it into a stream of tokens. A parser can be combined with an analyzer: see Parser : Analyzer, to produce a complete system for accepting input and parsing it.
See the package Classic for a good example of the use of this framework.
This documentation describes version 1.0 of Parsing.
The source code from which this documentation is derived is in the file Parsing.m2.