# 99 questions/Solutions/4

### From HaskellWiki

< 99 questions | Solutions(Difference between revisions)

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<haskell> | <haskell> | ||

myLength :: [a] -> Int | myLength :: [a] -> Int | ||

− | myLength = foldr (\ | + | myLength = foldr (\n x -> n + 1) 0 |

</haskell> | </haskell> | ||

This is <hask>length</hask> in <hask>Prelude</hask>. | This is <hask>length</hask> in <hask>Prelude</hask>. |

## 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

length

Prelude