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How to read Haskell

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-- something we can work through slowly (and show why we find it beautiful)
 
-- something we can work through slowly (and show why we find it beautiful)
 
</haskell>
 
</haskell>
  +
  +
=== Hint: use type signatures ===
  +
  +
When you see stuff like this
  +
<haskell>
  +
-- example please!
  +
foo :: Bar Ping Pong -> Baz Zed Dubya -> IO (DoublePlus Good)
  +
</haskell>
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...don't fight it! These are type signatures and they are an incredibly useful way of getting a rough idea what a function is supposed to do.
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  +
:''elaborate''
   
 
== What confuses non-Haskellers ==
 
== What confuses non-Haskellers ==

Revision as of 10:50, 3 August 2006

This stub is intended to become a tutorial on reading Haskell. It's aimed at the non-Haskeller who probably doesn't care too much about trying to write code, but wants to understand it.

1 The tutorial

...needs to be written

-- insert here some horrible (for the non-Haskeller) long example
-- something we can work through slowly (and show why we find it beautiful)

1.1 Hint: use type signatures

When you see stuff like this

-- example please!
foo :: Bar Ping Pong -> Baz Zed Dubya -> IO (DoublePlus Good)

...don't fight it! These are type signatures and they are an incredibly useful way of getting a rough idea what a function is supposed to do.

elaborate

2 What confuses non-Haskellers

Since this tutorial is not yet written, we encourage you to note here the things which confuse non-Haskellers about the code code.

  • layout instead of semicolons?
  • super-super-concise stuff (things using liftM and liftM2)
  • the difference between
    x <- foo
    and
    x = foo