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m (Replaced the link for the state doc with a better one)
(Corrected broken links and solved warnings given by http://validator.w3.org/checklink ; added a link to "A tour of the Haskell Monad functions")
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Library code usually differs from application code: it is often highly
 
Library code usually differs from application code: it is often highly
structured, and documented with [http://haskell.org/haddock haddock],
+
structured, and documented with [http://haskell.org/haddock/ haddock],
 
and can be rather optimised. Some instructive examples (syntax
 
and can be rather optimised. Some instructive examples (syntax
 
highlighting by [http://www.cs.york.ac.uk/fp/darcs/hscolour/ hscolour]):
 
highlighting by [http://www.cs.york.ac.uk/fp/darcs/hscolour/ hscolour]):
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* [http://www.cse.unsw.edu.au/~dons/data/Monad.html Monad.hs], basic monad support ([http://darcs.haskell.org/packages/base/Control/Monad.hs raw], [http://haskell.org/ghc/docs/latest/html/libraries/base/Control-Monad.html docs])
 
* [http://www.cse.unsw.edu.au/~dons/data/Monad.html Monad.hs], basic monad support ([http://darcs.haskell.org/packages/base/Control/Monad.hs raw], [http://haskell.org/ghc/docs/latest/html/libraries/base/Control-Monad.html docs])
 
* [http://www.cse.unsw.edu.au/~dons/data/QuickCheck.html QuickCheck.hs], a testing framework ([http://darcs.haskell.org/packages/QuickCheck/Test/QuickCheck.hs raw], [http://haskell.org/ghc/docs/latest/html/libraries/QuickCheck/Test-QuickCheck.html docs])
 
* [http://www.cse.unsw.edu.au/~dons/data/QuickCheck.html QuickCheck.hs], a testing framework ([http://darcs.haskell.org/packages/QuickCheck/Test/QuickCheck.hs raw], [http://haskell.org/ghc/docs/latest/html/libraries/QuickCheck/Test-QuickCheck.html docs])
* [http://www.cse.unsw.edu.au/~dons/data/HughesPJ.html PrettyPrint.hs], a pretty printing library ([http://darcs.haskell.org/packages/base/Text/PrettyPrint/HughesPJ.hs raw], [http://haskell.org/ghc/docs/latest/html/libraries/base/Text-PrettyPrint-HughesPJ.html docs])
+
* [http://www.cse.unsw.edu.au/~dons/data/HughesPJ.html PrettyPrint.hs], a pretty printing library ([http://darcs.haskell.org/ghc-6.6/packages/base/Text/PrettyPrint/HughesPJ.hs raw], [http://haskell.org/ghc/docs/latest/html/libraries/base/Text-PrettyPrint-HughesPJ.html docs])
 
* [http://www.cse.unsw.edu.au/~dons/data/State.html State.hs], a state monad ([http://darcs.haskell.org/packages/mtl/Control/Monad/State.hs raw], [http://haskell.org/ghc/docs/latest/html/libraries/mtl/Control-Monad-State-Lazy.html docs])
 
* [http://www.cse.unsw.edu.au/~dons/data/State.html State.hs], a state monad ([http://darcs.haskell.org/packages/mtl/Control/Monad/State.hs raw], [http://haskell.org/ghc/docs/latest/html/libraries/mtl/Control-Monad-State-Lazy.html docs])
 
* [http://www.cse.unsw.edu.au/~dons/data/Music.html Music.hs], a music composition system (literate latex-style Haskell) ([http://darcs.haskell.org/haskore/src/Haskore/Music.lhs raw], [http://haskell.org/haskore/ home])
 
* [http://www.cse.unsw.edu.au/~dons/data/Music.html Music.hs], a music composition system (literate latex-style Haskell) ([http://darcs.haskell.org/haskore/src/Haskore/Music.lhs raw], [http://haskell.org/haskore/ home])
 
* [http://www.ninebynine.org/Software/Swish-0.2.1/HaskellRDF/Dfa/Dfa.lhs Dfa.lhs], finite automata (literate Bird-style Haskell)
 
* [http://www.ninebynine.org/Software/Swish-0.2.1/HaskellRDF/Dfa/Dfa.lhs Dfa.lhs], finite automata (literate Bird-style Haskell)
* [http://www.cse.unsw.edu.au/~dons/data/RedBlackTree.html RedBlackTree.hs], a red-black tree ([http://www.polyomino.f2s.com/david/haskell/hs/redblacktree.hs.txt raw])
+
* [http://www.cse.unsw.edu.au/~dons/data/RedBlackTree.html RedBlackTree.hs], a red-black tree ([http://www.polyomino.f2s.com/david/haskell/hs/RedBlackTree.hs.txt raw])
 
* [http://www.cse.unsw.edu.au/~dons/data/Prime.html Prime.hs], prime numbers ([http://andrew.bromage.org/darcs/numbertheory/Math/Prime.hs raw])
 
* [http://www.cse.unsw.edu.au/~dons/data/Prime.html Prime.hs], prime numbers ([http://andrew.bromage.org/darcs/numbertheory/Math/Prime.hs raw])
 
* [http://www.cse.unsw.edu.au/~dons/data/Foldable.html Foldable.hs], traversable data structures ([http://darcs.haskell.org/packages/base/Data/Foldable.hs raw])
 
* [http://www.cse.unsw.edu.au/~dons/data/Foldable.html Foldable.hs], traversable data structures ([http://darcs.haskell.org/packages/base/Data/Foldable.hs raw])
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monadic IO, and sometimes other advanced features such as concurrency:
 
monadic IO, and sometimes other advanced features such as concurrency:
   
* [http://www.abridgegame.org/repos/darcs-unstable/PatchCommute.lhs Darcs], a revision control system (uses literate latex Haskell style) ([http://darcs.net home])
+
* [http://nanardon.zarb.org/darcs/darcs/PatchCommute.lhs Darcs], a revision control system (uses literate latex Haskell style) ([http://darcs.net home])
 
* [http://svn.openfoundry.org/pugs/src/Pugs/Eval.hs Pugs], a perl6 implementation ([http://pugscode.org home])
 
* [http://svn.openfoundry.org/pugs/src/Pugs/Eval.hs Pugs], a perl6 implementation ([http://pugscode.org home])
 
* [http://www.cse.unsw.edu.au/~dons/code/yi/Yi/Core.hs Yi], a text editor, ([http://www.cse.unsw.edu.au/~dons/yi.html home])
 
* [http://www.cse.unsw.edu.au/~dons/code/yi/Yi/Core.hs Yi], a text editor, ([http://www.cse.unsw.edu.au/~dons/yi.html home])
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* [http://darcs.haskell.org/~lemmih/downNova/src/Torrent.hs DownNova], a file downloading program
 
* [http://darcs.haskell.org/~lemmih/downNova/src/Torrent.hs DownNova], a file downloading program
 
* [http://www.cs.york.ac.uk/fp/darcs/cpphs/Language/Preprocessor/Cpphs/Tokenise.hs cpphs], an implementation of the C preprocessor ([http://www.cs.york.ac.uk/fp/cpphs/ home])
 
* [http://www.cs.york.ac.uk/fp/darcs/cpphs/Language/Preprocessor/Cpphs/Tokenise.hs cpphs], an implementation of the C preprocessor ([http://www.cs.york.ac.uk/fp/cpphs/ home])
* [http://darcs.haskell.org/ghc/compiler/simplCore/Simplify.lhs GHC], a Haskell compiler (literate latex style) ([http://haskell.org/ghc home])
+
* [http://darcs.haskell.org/ghc/compiler/simplCore/Simplify.lhs GHC], a Haskell compiler (literate latex style) ([http://haskell.org/ghc/ home])
* [http://www.augustsson.net/Darcs/Djinn/LJT.hs Djinn], a theorem prover ([http://darcs.augustsson.net/Darcs/Djinn home])
+
* [http://www.augustsson.net/Darcs/Djinn/LJT.hs Djinn], a theorem prover ([http://darcs.augustsson.net/Darcs/Djinn/ home])
 
* [http://darcs.haskell.org/c2hs/c2hs/c/CTrav.hs c2hs], a C to Haskell interface generator ([http://www.cse.unsw.edu.au/~chak/haskell/c2hs/ home])
 
* [http://darcs.haskell.org/c2hs/c2hs/c/CTrav.hs c2hs], a C to Haskell interface generator ([http://www.cse.unsw.edu.au/~chak/haskell/c2hs/ home])
 
* [http://www.cse.unsw.edu.au/~dons/code/lambdabot/LBState.hs Lambdabot], an IRC bot ([http://www.cse.unsw.edu.au/~dons/lambdabot.html home])
 
* [http://www.cse.unsw.edu.au/~dons/code/lambdabot/LBState.hs Lambdabot], an IRC bot ([http://www.cse.unsw.edu.au/~dons/lambdabot.html home])
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; [[Tying the Knot]] : An example that illustrates different ways to define recursive data structures. The example defines a simple language (illustrating how to define some recursive structures) and an interpreter for the language (illustrating how to work with the recursive structures).
 
; [[Tying the Knot]] : An example that illustrates different ways to define recursive data structures. The example defines a simple language (illustrating how to define some recursive structures) and an interpreter for the language (illustrating how to work with the recursive structures).
   
  +
; [http://members.chello.nl/hjgtuyl/tourdemonad.html A tour of the Haskell Monad functions] : Small usage examples of the basic Haskell monad functions
   
 
[[Category:Code]]
 
[[Category:Code]]

Revision as of 15:15, 20 July 2007

To get a feel for what real world Haskell looks like, here are some examples from various popular Haskell projects. To start learning the language, good places to start are here, here and here.

More code may be found on the wiki.


1 Library code

Library code usually differs from application code: it is often highly structured, and documented with haddock, and can be rather optimised. Some instructive examples (syntax highlighting by hscolour):

2 Application code

Code from popular Haskell applications. Such code often makes use of a monadic IO, and sometimes other advanced features such as concurrency:

3 Examples

Tying the Knot 
An example that illustrates different ways to define recursive data structures. The example defines a simple language (illustrating how to define some recursive structures) and an interpreter for the language (illustrating how to work with the recursive structures).
A tour of the Haskell Monad functions 
Small usage examples of the basic Haskell monad functions