Haskell code showing how pattern matching can make your code cleaner

pattern_matching_example.hs

-- a long  function to tell you what your number is or
-- if it's bigger than 5
onetofive :: (Integral a) => a -> String
onetofive x = do
	if x == 1 then
		"One!"
	else
		if x == 2 then
			"Two!"
		else
			if x == 3 then
				"Three!"
			else
				if x == 4 then
					"Four!"
				else
					if x == 5 then
						"Five!"
					else
						"A number bigger than five!"

-- a much neater function that does the same thing using pattern matching
onetofivebetter :: (Integral a) => a -> String
onetofivebetter 1 = "One!"
onetofivebetter 2 = "Two!"
onetofivebetter 3 = "Three!"
onetofivebetter 4 = "Four!"
onetofivebetter 5 = "Five!"
onetofivebetter x = "A number bigger than five!"

main = do
	print (onetofive 2)
	print (onetofive 8)
	print ""
	-- pattern matching function has same output
	print (onetofivebetter 2)
	print (onetofivebetter 8)