Type Functions in GHC
The main development repo of GHC now includes an extended version of the typed intermediate language, Core, that includes a notion of type equality coercions with the aim to support a whole range of source language features that make essential use of non-syntactic equality, such as GADTs, associated types, functional dependencies, and even general type functions.
We previously introduced an extension of type classes with type-indexed data types, called associated data types, and type functions, called associated type synonyms. FC enables us to generalise associated types to a general form of open type functions.
Documentation is available from the GHC Developer Wiki:
Getting the implementation
To grab the current implementations, do the following:
% darcs get --partial http://darcs.haskell.org/ghc/ % cd ghc % chmod +x ./darcs-all % ./darcs-all get
Then, follow the HACKING instructions.
|• Copyright 2005 Manuel M T Chakravarty • Last modified: Sun Oct 1 18:05:32 EDT 2006 •|