The compdata package

[Tags:benchmark, bsd3, library, test]

This library implements the ideas of Data types a la carte (Journal of Functional Programming, 18(4):423-436, 2008, as outlined in the paper Compositional data types (Workshop on Generic Programming, 83-94, 2011, The purpose of this library is to allow the programmer to construct data types -- as well as the functions defined on them -- in a modular fashion. The underlying idea is to separate the signature of a data type from the fixed point construction that produces its recursive structure. Signatures can then be composed and decomposed freely.

Building on that foundation, this library provides additional extensions and (run-time) optimisations which make compositional data types usable for practical implementations. In particular, it provides an excellent framework for manipulating and analysing abstract syntax trees in a type-safe manner. Thus, it is perfectly suited for programming language implementations, especially, in an environment consisting of a family of tightly interwoven domain-specific languages.

In concrete terms, this library provides the following features:

Examples of using (generalised) compositional data types are bundled with the package in the folder examples.

Previous versions of this library contained a parametric variant of compositional data types. This former part of the library has been moved to a separate package: compdata-param


Versions 0.1, 0.2, 0.3, 0.4, 0.4.1, 0.5, 0.5.1, 0.5.2, 0.5.3, 0.6, 0.6.1,,,,, 0.7,,, 0.8,,,,,, 0.9, 0.10, 0.10.1, 0.11
Dependencies base (>=4.7 && <5), containers, deepseq, derive, mtl, QuickCheck (>=2), template-haskell, th-expand-syns, transformers, tree-view [details]
License BSD3
Author Patrick Bahr, Tom Hvitved
Category Generics
Bug tracker
Source repository head: git clone
Uploaded Sat Aug 9 10:40:24 UTC 2014 by PatrickBahr
Distributions NixOS:0.11
Downloads 6451 total (30 in the last 30 days)
0 []
Status Docs uploaded by user
Build status unknown [no reports yet]
Hackage Matrix CI




Maintainer's Corner

For package maintainers and hackage trustees