Haddock (software)

Haddock is a free, portable^[1] command-line program documentation generator for Haskell.

Haddock
Developer	Simon Marlow
Initial release	May 1, 2002
Stable release	2.25.0  / 2 March 2021; 4 years ago (2 March 2021)
Repository	github.com/haskell/haddock
Written in	Haskell
Operating system	Cross-platform
Platform	x86, PowerPC
Type	Documentation generation
License	BSD-style license
Website	http://haskell.org/haddock/

Software

It is influenced by IDoc,^[2] HDoc,^[3] and Doxygen.^[4] It produces hyperlinked HTML files from annotated Haskell (the documentation is embedded in comments) source files, with additional information extracted from type annotations; it supports only partially generating documentation in SGML.^[5] It is often used in conjunction with darcs and Cabal. It is dependent on Glasgow Haskell Compiler (GHC), using a modified form of the HsParser (written in Happy) parser for Haskell included in GHC.^[5] Its lightweight markup is based on IDoc's.^[5] Haddock is contained in the Haskell Platform.

It is used by the GHC, Gtk2Hs and HTk projects,^[6] as well as xmonad.^{[citation needed]}

Here is an example of Haddock markup:

 -- | This is the documentation for 'square', which
 --   uses the (*) operator from "Prelude".
 --   It multiplies the @x@ argument against itself.
 square :: Integer -> Integer
 square x = x*x