Extensible and Modular Generics for the Masses.

EMGM is a general-purpose library for datatype-generic programming.

The design is based on the idea of modeling algebraic datatypes as sum-of-product structures. Many datatypes can be modeled this way, and because they all share a common structure, we can write generic functions that work on this structure.

The primary features of the library are:

• A foundation for building generic functions. EMGM includes a collection of datatypes (e.g. sum, product, and unit) and type classes (e.g. Generic and Rep). Everything you need for defining generic functions and supporting datatypes can be found here.

• Many useful generic functions. These provide a wide range of functionality. For example, there is crush, a generalization of the foldl/foldr functions, that allows you to flexibly extract the elements of a polymorphic container. Now, you can do many of the operations with your container that were previously only available for lists.

• Support for standard datatypes. EMGM supports standard types: primitives (e.g. Int and Float), Bool, lists, tuples, Maybe, etc.

NOTE: As of version 0.4, this library does not have Template Haskell for generating the representation. We are working on another library for a solution to this problem.

Extensible and Modular Generics for the Masses

Extensible and Modular Generics for the Masses (EMGM) is a library for generic programming in Haskell.

Features

The primary features of EMGM include:

• Datatype-generic programming using sum-of-product views
• Large collection of ready-to-use generic functions
• Included support for standard datatypes: lists, Maybe, tuples
• Easy to add support for new datatypes
• Type classes make writing new functions straightforward in a structurally inductive style
• Generic functions are extensible with ad-hoc cases for arbitrary datatypes
• Good performance of generic functions

The features of this distribution include:

• The API is thoroughly documented with Haddock
• Fully tested with QuickCheck and HUnit
• Program coverage ensures that all useful code has been touched by tests

Examples

You can find examples of using EMGM in the examples directory of the source distribution.

Bugs & Support

To report bugs, use the Google Code project page for EMGM.

For general concerns and questions, use the Generics mailing list.