Here is small collection of my ghci scripts taken from different places. For complete file see my dotfiles.

Pointfree

Convert expression into pointfree style. You need to have pointree package installed in order to use this function (in case of Gentoo run emerge dev-haskell/pointfree).

-- pointfree
:def pf \str -> return $ ":! pointfree \"" ++ str ++ "\""

Haskell-docs

Show documentation on given function. In order to use it you need to intall haskell-doc package and built documentation for packages.

In Gentoo case: 1. echo ‘dev-haskell/* docs’ >> /etc/portage/package.use 2. emerge dev-haskell/haskell-docs

-- documentation
:def doc \input -> return (":!haskell-docs " ++ input)

The format is following: []

:doc System.IO getContents base The getContents operation returns all user input as a single string, which is read lazily as it is needed (same as hGetContents stdin).

GHC-Vis

A great tool to show how expressions will be presented in memory. You can use it in order to understand your data structure and laziness/strictness of expressions. As usual you need to install ghc-vis package. Documentation for package (nice pictures included): http://felsin9.de/nnis/ghc-vis/

-- ghc-vis
:script //usr/share/ghc-vis-0.7.1/ghc-7.6.3/ghci

Hoogle

To enable searching with hoogle (either local or global) you can install hoogle package.

:def hoogle \str -> return $ ":! hoogle --count=15 \"" ++ str ++ "\""

Prompt

To hide a big list of imported modules and have a nice look’n’feel you can change you ghci prompt.

:set prompt "λ> "

To see list of imported modules you can type: :show imports.

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