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Module: List
Function: find
Type: (a -> Bool) -> [a] -> Maybe a
Description: Function find returns the first element of a list that satisfies a predicate, or Nothing, if there is no such element. findIndex returns the corresponding index. findIndices returns a list of all such indices.
Related: elemIndex, elemIndices, findIndex, findIndices

Example 1

Input: find (>3) [0,2,4,6,8]

Output: Just 4

Example 2

Input: find (==3) [0,2,4,6,8]

Output: Nothing

Example 3

Input: find even [2,4,6,8]

Output: Just 2

Example 4

Input: find (\x -> 5**x > 10000) [2,4,6,8]

Output: Just 6.0