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Cookbook/Interactivity

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== Input and output ==
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{| class="wikitable"
 
{| class="wikitable"
 
|-
 
|-
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</haskell>
 
</haskell>
 
|-
 
|-
|  printing a string in a new line
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|  printing a string with a newline character
 
|  [http://haskell.org/ghc/docs/latest/html/libraries/base/Prelude.html#v%3AputStrLn putStrLn]
 
|  [http://haskell.org/ghc/docs/latest/html/libraries/base/Prelude.html#v%3AputStrLn putStrLn]
 
|<haskell>
 
|<haskell>
 
Prelude> putStrLn "Foo"
 
Prelude> putStrLn "Foo"
 
Foo
 
Foo
 +
Prelude>
 
</haskell>
 
</haskell>
 
|-
 
|-
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|}
 
|}
  
== Printing a string ==
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Strings can be output in a number of different ways.
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<haskell>
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Prelude> putStr "Foo"
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FooPrelude>
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</haskell>
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As you can see, [http://haskell.org/ghc/docs/latest/html/libraries/base/Prelude.html#v%3AputStr putStr] does not include the newline character `\n'.  We can either use putStr like this:
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<haskell>
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Prelude> putStr "Foo\n"
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Foo
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</haskell>
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Or use [http://haskell.org/ghc/docs/latest/html/libraries/base/Prelude.html#v%3AputStrLn putStrLn], which is already in the Standard Prelude
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<haskell>
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Prelude> putStrLn "Foo"
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Foo
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</haskell>
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We can also use [http://haskell.org/ghc/docs/latest/html/libraries/base/Prelude.html#v%3Aprint print] to print a string, '''including the quotation marks.'''
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<haskell>
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Prelude> print "Foo"
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"Foo"
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</haskell>
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== Parsing command line arguments ==
 
== Parsing command line arguments ==
  
 
TODO
 
TODO

Revision as of 09:08, 2 August 2009

1 Input and output

Problem Solution Examples
printing a string putStr
Prelude> putStr "Foo"
FooPrelude>
printing a string with a newline character putStrLn
Prelude> putStrLn "Foo"
Foo
Prelude>
reading a string getLine
Prelude> getLine
Foo bar baz          --> "Foo bar baz"


2 Parsing command line arguments

TODO