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Cookbook/Interactivity

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= Reading a string =
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== Reading a string ==
 
Strings can be read as input using [http://haskell.org/ghc/docs/latest/html/libraries/base/Prelude.html#v%3AgetLine getLine].
 
Strings can be read as input using [http://haskell.org/ghc/docs/latest/html/libraries/base/Prelude.html#v%3AgetLine getLine].
 
<haskell>
 
<haskell>
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</haskell>
 
</haskell>
   
= Printing a string =
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== Printing a string ==
 
Strings can be output in a number of different ways.
 
Strings can be output in a number of different ways.
 
<haskell>
 
<haskell>
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</haskell>
 
</haskell>
   
= Parsing command line arguments =
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== Parsing command line arguments ==
   
 
TODO
 
TODO

Revision as of 11:32, 9 July 2009

1 Reading a string

Strings can be read as input using getLine.

Prelude> getLine
Foo bar baz
"Foo bar baz"

2 Printing a string

Strings can be output in a number of different ways.

Prelude> putStr "Foo"
FooPrelude>

As you can see, putStr does not include the newline character `\n'. We can either use putStr like this:

Prelude> putStr "Foo\n"
Foo

Or use putStrLn, which is already in the Standard Prelude

Prelude> putStrLn "Foo"
Foo

We can also use print to print a string, including the quotation marks.

Prelude> print "Foo"
"Foo"

3 Parsing command line arguments

TODO