seven languages in seven weeks : haskell day 1

allEven.hs

module Main where
	allEvenWithRecursion :: [Integer] -> [Integer]
	allEvenWithRecursion [] = []
	allEvenWithRecursion (h:t) = if even h then h:allEvenWithRecursion t else allEvenWithRecursion t

	allEvenWithListComprehension :: [Integer] -> [Integer]
	allEvenWithListComprehension (numbers) = [x | x <- numbers , even x ] 

	allEvenWithFilter:: [Integer] -> [Integer]
	allEvenWithFilter  = filter even 
	
	allEvenWithFoldRight :: [Integer] -> [Integer]
	allEvenWithFoldRight = foldr (\x xs -> if even x then x:xs else xs) []

        allEvenWithFoldLeft :: [Integer] -> [Integer]
        allEvenWithFoldLeft = foldl (\x xs -> if even xs then x ++ [xs] else x) [] 

colorCombinations.hs

let colors= ["black", "white","blue","yellow","red"]
[(a,b) | a<-colors, b<-colors, a<=b]

coloring.hs

let colors= ["red" , "green" , "blue"]

 [("Alabama" ,alabamaColor, "Mississipi", mississipiColor, "Georgia", georgiaColor, "Tennessee", tennesseeColor, "Florida", floridaColor) | alabamaColor  <- colors, mississipiColor <- colors, georgiaColor <- colors, tennesseeColor <- colors, floridaColor <- colors, mississipiColor /= tennesseeColor, mississipiColor /= alabamaColor, alabamaColor /= tennesseeColor, alabamaColor /= georgiaColor, alabamaColor /= floridaColor,georgiaColor /= floridaColor, georgiaColor /= tennesseeColor]

multiplicationTable.hs

[(factor,multiplier,factor * multiplier)| factor <- numbers, multiplier <- numbers] 

reverseList.hs

reverseList :: [a] -> [a]
    	reverseList [] = []
 	reverseList (head:tail) = reverseList tail ++ [head]