The Glasgow Haskell Compiler 6.6

The Glasgow Haskell Compiler is a state-of-the-art, open source, compiler and interactive environment for the functional language Haskell.
Main features:
- GHC supports the entire Haskell 98 language plus a wide variety of extensions.
- GHC works on several platforms including Windows and most varieties of Unix, and several different processor architectures. There are detailed instructions for porting GHC to a new platform.
- GHC has extensive optimisation capabilities, including inter-module optimisation.
- GHC compiles Haskell code either by using an intermediate C compiler (GCC), or by generating native code on some platforms. The interactive environment compiles Haskell to bytecode, and supports execution of mixed bytecode/compiled programs.
- Profiling is supported, both by time/allocation and various kinds of heap profiling.
- GHC comes with a wide range of libraries.
GHC is heavily dependent on its users and contributors. Please come and join the mailing lists and send us your comments, suggestions, bug reports and contributions!
Enhancements:
- SMP support and impredicative polymorphism were added.
- The libraries were split into core and extra.
- Many more changes were made.