Haskell (programming language)

Haskell is a purely functional programming language. It is named after Haskell Brooks Curry, a U.S. mathematician who contributed a lot to logic. Haskell is based on lambda calculus and uses the Greek letter lambda as its logo. The main implementations are the Glasgow Haskell Compiler (GHC), and Hugs, a Haskell interpreter.

Examples

The following is an example Hello World program in Haskell:

module Main where
 
main :: IO ()
main = putStrLn "Hello, World!"

One way to create an infinite list of Fibonacci numbers is this:

fib n = fibs !! n
        where fibs = 0 : 1 : zipWith (+) fibs (tail fibs)