Good wiki book at http://en.wikibooks.org/wiki/Haskell

• Assignment is prefixed with 'let' in ghci but not in ghc or loaded .hs files
  
  • let x = 3
  • x = 3
    
• Assignment of the result of an IO action is via <-
  • x <- getLine
    
• Function declarations do NOT use parenthesis or comma.
  
  • funname parm1, parm2 = parm1 - 6 * parm2
• List literals use square brackets and commas; they can also be written with colons and an empty list
  
  • x = [1,2,3]
  • x = 1:2:3:[]
    
• List elements must have the same type (i.e. the list's type is "list of x" and not just "list")
• True/False are written in title case, and have type Bool.
  
  • True
  • False
• Strings use proper direct-quote marks. They have type 'list of Char' in addition to String.
  • "string"
    
• Characters use apostrophes (a.k.a.single-quotes)
  • 'x'
    
• Colon is used to prepend a single value to a list
  • value:list
• Tuples use parenthesis and commas and need not have elements of the same type
  • x = (1, "b", False)
• fst and snd retrieve the first and second items from a pair respectively (i.e. a 2-tuple)
• if statements are of the form:
  • if condition
    • then value
    • else value
• case statements are of the form:
  • case var of
    • pattern1 -> result1
    • pattern2 -> result2
    • _ -> result3
• Function composition: the following are equivalent
  
  • (f . g) x
  • f(g(x))
• Local variables:

let a = 3
     b = 2
in (blahblahblah,
     bleebleeblee) 

• type names are in title case
• Basic output:
  • putStrLn <string>
  • show <variable>
• To monadify something, use 'return'
  • return "abcd"
    
• To de-monadify something, use '<-'
  • x <- return "foo"
    
• (more coming)