Haddock: A Haskell Documentation Tool
This is Haddock, a tool for automatically generating documentation from annotated Haskell source code. It is primarily intended for documenting libraries, but it should be useful for any kind of Haskell code.

Haddock lets you write documentation annotations next to the definitions of functions and types in the source code, in a syntax that is easy on the eye when writing the source code (no heavyweight mark-up). The documentation generated by Haddock is fully hyperlinked - click on a type name in a type signature to go straight to the definition, and documentation, for that type.

Haddock understands Haskell's module system, so you can structure your code however you like without worrying that internal structure will be exposed in the generated documentation. For example, it is common to implement a library in several modules, but define the external API by having a single module which re-exports parts of these implementation modules. Using Haddock, you can still write documentation annotations next to the actual definitions of the functions and types in the library, but the documentation annotations from the implementation will be propagated to the external API when the documentation is generated. Abstract types and classes are handled correctly. In fact, even without any documentation annotations, Haddock can generate useful documentation from your source code.

Haddock can generate documentation in multiple formats; currently HTML is implemented, and there is partial support for generating LaTeX.

  • Haddock is being used to document the core libraries of GHC.. The latest version of the documentation is here.
  • Haddock is also used to document most packages on hackage.

Haddock is licensed under a BSD-style license

All current development (including issue tracking) takes place on github at https://github.com/haskell/haddock.

Feel free to hack on Haddock and send your patches.

  • The HackageDB page for the latest Haddock version
  • RPMs for Linux: RPMs can be built from the source distribution using rpmbuild -ta or from the source RPM using rpmbuild --rebuild, but you do need GHC installed.
  • FreeBSD/x86 and OpenBSD/x86: Haddock is in the ports tree, under devel/hs-haddock. To install binaries on FreeBSD, just say pkg_add -r hs-haddock.

Simon Marlow <simonmar@microsoft.com>