This document describes GHC's prelude and libraries. The basic story is that of the Haskell 1.4 Report and Libraries document (which we do not reproduce here), but this document describes in addition:
GHC's additional non-standard libraries and types, such as state transformers, packed strings, foreign objects, stable pointers, and so on.
GHC's primitive types and operations. The standard Haskell functions are implemented on top of these, and it is sometimes useful to use them directly.
The organisation of these libraries into directories.
Short description of programmer interface to the non-standard libraries provided in addition to the standard prelude.
A number of the libraries that provide access to GHC's language extensions are shared by Hugs, and are described in the GHC/Hugs Extension Libraries document.
GHC's prelude contains the following non-standard extensions:
It's there. Converts from an Int to the type.
Converts from Integral type to an Int.
GHC also internally uses a number of modules that begin with the string Prel: for this reason, we don't recommend that you use any module names beginning with Prel in your own programs. The Prel modules are always available: in fact, you can get access to several extensions this way (for some you might need to give the -fglasgow-exts flag).