A non-covering type family is a type family whose patterns do not cover the whole space.
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What are type families? | Types and Kinds a total type family is properly a function on types. Those other dependently typed languages have functions on types, and they seem to work nicely. I am completely unbothered by total type families.
Non-covering type families are strange
<span>A non-covering type family is a type family whose patterns do not cover the whole space. Let’s consider closed and open families separately, because the issues that come up are different.
Closed type families
For example:
> type family F1 a where
> F1 Int Summary
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