alex: Alex is a tool for generating lexical analysers in Haskell

[ bsd3, development, program ] [ Propose Tags ]
Versions 2.1.0, 2.2, 2.3, 2.3.1, 2.3.2, 2.3.3, 2.3.4, 2.3.5, 3.0, 3.0.1, 3.0.2, 3.0.3, 3.0.4, 3.0.5, 3.1.0, 3.1.1, 3.1.2, 3.1.3, 3.1.4, 3.1.5, 3.1.6, 3.1.7, 3.2.0, 3.2.1, 3.2.2, 3.2.3
Dependencies array, base (>=1.0 && <5), containers, directory, QuickCheck (>=2) [details]
License BSD-3-Clause
Copyright (c) Chis Dornan, Simon Marlow
Author Chris Dornan and Simon Marlow
Maintainer Simon Marlow <>
Category Development
Home page
Bug tracker
Source repo head: git clone
Uploaded by SimonMarlow at Wed Nov 25 10:25:38 UTC 2015
Distributions Arch:3.2.3, Debian:3.1.6, Fedora:3.2.3, FreeBSD:3.1.4, LTSHaskell:3.2.3, NixOS:3.2.3, Stackage:3.2.3, openSUSE:3.2.3
Executables alex
Downloads 103180 total (395 in the last 30 days)
Rating (no votes yet) [estimated by rule of succession]
Your Rating
  • λ
  • λ
  • λ
Status Docs not available [build log]
Last success reported on 2016-11-30 [all 5 reports]
Hackage Matrix CI

Alex is a tool for generating lexical analysers in Haskell. It takes a description of tokens based on regular expressions and generates a Haskell module containing code for scanning text efficiently. It is similar to the tool lex or flex for C/C++.

Changes in 3.1.5:

Changes in 3.1.4:

Changes in 3.1.3:

Changes in 3.1.2:

Changes in 3.1.1:

Changes in 3.1.0:

[Skip to Readme]



Choose the new smaller, split-up base package.


Use -f <flag> to enable a flag, or -f -<flag> to disable that flag. More info


Maintainer's Corner

For package maintainers and hackage trustees

Readme for alex-3.1.5

[back to package description]
		       Alex: A Lexical Analyser Generator

Alex is a Lex-like tool for generating Haskell scanners.  For complete
documentation, see the doc directory.

Alex is built using Cabal.  First install GHC, then:
  $ runhaskell Setup.lhs configure
  $ runhaskell Setup.lhs build
  $ runhaskell Setup.lhs install

Alex version 2.0 has changed fairly considerably since version 1.x,
and the syntax is almost completely different.  For a detailed list of
changes, see the release notes in the documentation.

Alex is now covered by a BSD-Style licence; see the licence file in
the `doc' directory for details.

The sources are in the the `src' directory and the documentation in the `doc'
directory; various  examples are in the 'examples' subdirectory.

The source code in the 'src' and 'examples' directories is intended
for a Haskell 98 compiler with hierarchical modules.  It should work
with GHC >= 5.04.

Please report any bugs or comments to the email addresses given below.

Share and enjoy,

Chris Dornan:
Isaac Jones:
Simon Marlow: