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Module: | Maybe |
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Function: | catMaybes |
Type: | [Maybe a] -> [a] |
Description: | creates a list of Just values from a Maybe list |
Related: |
Program source: a = [(1,'A'),(2,'B'),(3,'C')]
Input: catMaybes [lookup 0 a, lookup 1 a, lookup 3 a, lookup 12 a]
Output: "AC"
Program source: b = [(1,11),(2,22),(3,33)]
Input: catMaybes [lookup 0 b, lookup 1 b, lookup 3 b, lookup 12 b]
Output: [11,33]