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[[Category:How to]]
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== Haskell Cookbook ==
 
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* [[Cookbook/Compilers and interpreters|Haskell compilers and interpreters]]
* [[Cookbook/Strings|Strings]]
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* [[Cookbook/Numbers|Numbers]]
 
* [[Cookbook/Numbers|Numbers]]
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* [[Cookbook/Lists and strings|Lists and strings]]
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* [[Cookbook/Other data structures|Other data structures]]
 
* [[Cookbook/Dates And Time|Dates and time]]
 
* [[Cookbook/Dates And Time|Dates and time]]
* [[Cookbook/Lists|Lists]]
 
* [[Cookbook/Other data structures|Other data structures]]
 
 
* [[Cookbook/Pattern matching|Pattern matching]]
 
* [[Cookbook/Pattern matching|Pattern matching]]
 
* [[Cookbook/Interactivity|Interactivity]]
 
* [[Cookbook/Interactivity|Interactivity]]
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* [[Cookbook/Testing|Testing]]
 
* [[Cookbook/Testing|Testing]]
  
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== Similar projects for other programming languages ==
 
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* [http://cl-cookbook.sourceforge.net/ Common Lisp Cookbook]
'''We need to start a Haskell centered cookbook (aka, not a [http://pleac.sourceforge.net/ PLEAC] clone)
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* [http://pleac.sourceforge.net/ PLEAC]
 
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* [http://www.zenspider.com/Languages/Ruby/Cookbook/index.html Ruby Cookbook]
This page is based on the Scheme Cookbook at
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* [http://schemecookbook.org/Cookbook/WebHome Scheme Cookbook]
http://schemecookbook.org/Cookbook/WebHome'''
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* [http://fssnip.net/ F# Snippets]
== Prelude ==
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[[Category:FAQ]]
 
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[[Category:How to]]
A lot of functions are defined in the "[http://www.haskell.org/hoogle/?q=Prelude Prelude]". Also, if you ever want to search for a function, based on the name, type or module, take a look at the excellent [http://www.haskell.org/hoogle/ Hoogle]. This is for a lot of people a must-have while debugging and writing Haskell programs.
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== GHCi/Hugs ==
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=== GHCi interaction ===
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To start GHCi from a command prompt, simply type `ghci'
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    $ ghci
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      ___        ___ _
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      / _ \ /\  /\/ __(_)
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    / /_\// /_/ / /  | |      GHC Interactive, version 6.6, for Haskell 98.
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    / /_\\/ __  / /___| |      http://www.haskell.org/ghc/
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    \____/\/ /_/\____/|_|      Type :? for help.
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    Loading package base ... linking ... done.
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    Prelude>
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[http://haskell.org/ghc/docs/latest/html/libraries/base/Prelude.html Prelude] is the "base" library of Haskell.
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To create variables at the GHCi prompt, use `let'
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<haskell>
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Prelude> let x = 5
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Prelude> x
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5
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Prelude> let y = 3
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Prelude> y
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3
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Prelude> x + y
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8
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</haskell>
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`let' is also the way to create simple functions at the GHCi prompt
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<haskell>
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Prelude> let fact n = product [1..n]
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Prelude> fact 5
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120
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</haskell>
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=== Checking Types ===
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To check the type of an expression or function, use the command `:t'
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<haskell>
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Prelude> :t x
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x :: Integer
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Prelude> :t "Hello"
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"Hello" :: [Char]
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</haskell>
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Haskell has the following types defined in the [http://haskell.org/ghc/docs/latest/html/libraries/base/Prelude.html Standard Prelude].
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<haskell>
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    Int        -- bounded, word-sized integers
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    Integer    -- unbounded integers
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    Double      -- floating point values
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    Char        -- characters
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    String      -- equivalent to [Char], strings are lists of characters
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    ()          -- the unit type
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    Bool        -- booleans
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    [a]         -- lists
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    (a,b)      -- tuples / product types
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    Either a b  -- sum types
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    Maybe a    -- optional values
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</haskell>
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Latest revision as of 18:49, 26 May 2011

[edit] 1 Haskell Cookbook

[edit] 2 Similar projects for other programming languages