Haskell Pretty-printer library
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Pretty : A Haskell Pretty-printer library

Hackage Hackage Dependencies BSD3 License Build

Pretty is a pretty-printing library, a set of API's that provides a way to easily print out text in a consistent format of your choosing. This is useful for compilers and related tools.

It is based on the pretty-printer outlined in the paper 'The Design of a Pretty-printing Library' by John Hughes in Advanced Functional Programming, 1995. It can be found here.


This library is BSD-licensed.


The library uses the Cabal build system, so building is simply a matter of running:

cabal sandbox init
cabal install "QuickCheck >= 2.5 && < 3"
cabal install --only-dependencies
cabal configure --enable-tests
cabal build
cabal test

We have to install QuickCheck manually as otherwise Cabal currently throws an error due to the cyclic dependency between pretty and QuickCheck.

If cabal test freezes, then run cabal test --show-details=streaming instead. This is due to a bug in certain versions of Cabal.

Get involved!

We are happy to receive bug reports, fixes, documentation enhancements, and other improvements.

Please report bugs via the github issue tracker.

Master git repository:

  • git clone git://github.com/haskell/pretty.git


This library is maintained by David Terei, code@davidterei.com. It was originally designed by John Hughes's and since heavily modified by Simon Peyton Jones.