The use of `class` for things that should be simple free functions

Re:The use of `class` for things that should be simple free ... by js8 on Thursday May 28, 2020 @05:57AM (#23335473)

In Haskell typeclasses, it's the type of the parameter that is implicitly passed, not the parameter itself.

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Re:The use of `class` for things that should be simple free ... by uryga on Thursday May 28, 2020 @06:09AM (#23335546)

i don't think that's correct, afaik typeclasses roughly desugar to passing a record of functions (vtable/"dictionary") at the call site

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Re:The use of `class` for things that should be simple free ... by taejo on Thursday May 28, 2020 @06:31AM (#23335684)

And that vtable depends on the type, not the value.

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Re:The use of `class` for things that should be simple free ... by uryga on Thursday May 28, 2020 @12:36PM (#23339301)

i guess there's really two implicit arguments - the value's type, `a` (quantified via forall - the System F "Λ") and its vtable `Show a`... though i guess the vtable is uniquely determined by the type bc in Haskell instances are globally unique

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