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A comment on Why Haskell?. Parent comment

Re:Why Haskell? by remexre on Thursday September 12, 2024 @10:05PM (#41527455)
The infinite loop case is:

    loopType : Int -> Type
    loopType x = loopType x

    foo : List (loopType 3) -> Int
    foo _ = 42

    bar : List (loopType 4)
    bar = []

    baz : Int
    baz = foo bar
Determining if baz type-checks requires evaluating loopType 3 and loopType 4 to determine if they're equal.
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Re:Why Haskell? by HelloNurse on Friday September 13, 2024 @08:03AM (#41530380)
Given line "loopType : Int -> Type", how can line "loopType x = loopType x" mean anything useful? It should be rejected and ignored as a tautology, leaving loopType undefined or defined by default as a distinct unique value for each int.
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Re:Why Haskell? by remexre on Friday September 13, 2024 @02:13PM (#41533651)
What makes it ill-defined is that it computes infinitely -- that's why you need a totality checker (or a total language).
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