99 questions/Solutions/4

(Difference between revisions)

Revision as of 01:15, 15 September 2010

(*) Find the number of elements of a list.

myLength           :: [a] -> Int
myLength []        =  0
myLength (_:xs)    =  1 + myLength xs

myLength :: [a] -> Int
myLength =  foldr (\n x -> n + 1) 0

This is

length

Prelude

@@ Line 9: / Line 9: @@
 <haskell>
 myLength :: [a] -> Int
-myLength =  foldr (\x n -> n + 1) 0
+myLength =  foldr (\n x -> n + 1) 0
 </haskell>
 This is <hask>length</hask> in <hask>Prelude</hask>.