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| Module: | List |
|---|---|
| Function: | elemIndex |
| Type: | Eq => a -> [a] -> Maybe Int |
| Description: | returns the index of the first occurrence, if any, of value in list. |
| Related: | elemIndices, find, findIndex, findIndices |
Input: elemIndex 2 [1,2,3,4,5]
Output: Just 1
Input: elemIndex 2 [2,2,2,3,3,3,4,4,4]
Output: Just 0
Input: elemIndex 10 [1,2,3,4,5]
Output: Nothing
Input: elemIndex 'f' "abcdefghi"
Output: Just 5