maybe a type Test (c :: Constraint) = c => () is in order here ;) testTheObvious... | Hacker News

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		whateveracct on Sept 14, 2021 \| parent \| context \| favorite \| on: An Introduction to Type Level Programming in Haske... maybe a `type Test (c :: Constraint) = c => ()` is in order here ;) `testTheObvious :: Test ((2 + 2) ~ 5) testTheObvious = ()`

tome on Sept 15, 2021 [–]

That compiles though. You need to CPS the constraint as in my example above. This does the job:

    type Test (c :: Constraint) = forall a. (c => a) -> a
    
    testTheObvious :: Test ((2 + 2) ~ 5)
    testTheObvious = id

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