@hackage FormalGrammars0.4.0.0

generalized Algebraic Dynamic Programming

Context-free grammars in formal language theory are sets of production rules, non-terminal and terminal symbols. This library provides basic data types and functions to manipulate such grammars.

Grammars can be defined in a small domain-specific language that is very close to typical CFG notation. The DSL parser can easily be extended. Grammar products, for example, are implemented as a single additional sub-parser.

This library also provides the machinery that transforms an Inside grammar into the corresponding Outside grammar.

Starting with version 0.2.1 it is possible to write multiple context-free grammars within this framework.

In addition, TemplateHaskell and QuasiQuoting functionality allow embedding thusly defined grammars in Haskell programs. ADPfusion then turns such a grammar into an efficient dynamic program. It is also possible to generate Haskell modules that contain the resulting grammar, signature and algebra product.

Alternatives are ansi- or LaTeX-based pretty-printing for users that want to implement their CFG in another language than Haskell.

Formal background can be found in a number of papers which are given in the README.