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| Module: | Prelude |
|---|---|
| Function: | lookup |
| Type: | Eq a => a -> [(a,b)] -> Maybe b |
| Description: | |
| Related: |
Input: lookup 'c' [('a',0),('b',1),('c',2)]
Output: Just 2
Input: lookup 'c' [('a',0),('b',1),('c',2),('a',3),('b',4),('c',5)]
Output: Just 2
Input: lookup 'f' [('a',0),('b',1),('c',2)]
Output: Nothing