Difference between revisions of "Cookbook/Interactivity"

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== Printing a string ==
 
Strings can be output in a number of different ways.
 
<haskell>
 
Prelude> putStr "Foo"
 
FooPrelude>
 
</haskell>
 
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:
 
<haskell>
 
Prelude> putStr "Foo\n"
 
Foo
 
</haskell>
 
Or use [http://haskell.org/ghc/docs/latest/html/libraries/base/Prelude.html#v%3AputStrLn putStrLn], which is already in the Standard Prelude
 
<haskell>
 
Prelude> putStrLn "Foo"
 
Foo
 
</haskell>
 
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.'''
 
<haskell>
 
Prelude> print "Foo"
 
"Foo"
 
</haskell>
 
   
 
== Parsing command line arguments ==
 
== Parsing command line arguments ==

Revision as of 09:04, 2 August 2009

Problem Solution Examples
printing a string putStr
Prelude> putStr "Foo"
FooPrelude>
printing a string in a new line putStrLn
Prelude> putStrLn "Foo"
Foo
reading a string getLine
Prelude> getLine
Foo bar baz          --> "Foo bar baz"


Parsing command line arguments

TODO