Re:SELECT wat FROM sql
by ericpauley on Monday April 27, 2020 @12:55AM
(#22992994)
This doesn't really solve GP's problem, as the Nothing type is generally still equal to itself. Certainly useful for general purpose programming languages, though.
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The problem is really that you're using the wrong equality type here. You get the right semantics if you use `= : A -> A -> Bool` and then apply it to a `Maybe A` and a `Maybe A` by lifting it: you end up with `Nothing` if either input was `Nothing`, and `Just answer` if both were known.