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FACSKELL is the Founders & Coders Haskell Club. We are currently learning Haskell by readingCIS 194: Introduction to Haskell (Spring 2013) byBrent Yorgey. We are also learning from other books:

• Learn you a Haskell for great good
• Real world Haskell

Find and post your questions onReddit Haskell,Reddit Haskell Questions or onStackoverflow

For a more detail list of documentation you can have a look at theHaskell website

Because learning Haskell is cool!

Haskell is:

• Functional
• Pure
  • Immutable
  • No side effects
  • A same function with the same arguments will return the same outputs
• Lazy
• Typed

Haskell has the usual types : Bool, Int, Integer, Char, String. The Char type is represented with single quote 'C', the Sting type is represented with double quotes "myString". Haskell has also some more useful types:

• Pairs:

p:: (Int,Char)

• List:

l:: [Integer]-- a list is a head and a tail (x:xs)

You can use the keywordtype to create an alias for a type.

typeSt=Stringf::St->St

You can create a new type with the keyworddata:

dataTree=Empty |LeafInt |NodeTreeTree

Here we create thetype constructor Tree whith the followingdata constructors:

• Empty
• Leaf Int
• Node Tree Tree

Leaf and Node take parameters!type constructor and data constructor must begin with a capital letter!

You can combine functions:

 myOtherFunc (myFirstFunc a)

Two useful operators:

. Which correspond to the mathematic composition. The result of the fist function become the input of the second function

(myOtherFunc. myFirstFunc) a

$ Replace parenthesis. Everything after $ will be executed before the things before the $ (everything after $ has a higher precedence)

myOtherFunc$ myFirstFunc a

Haskell load by default the Prelude module which contains a lot of useful functions

You can find all the documentation of Haskell on Hoogle