Are there languages that have first class associative product / sum types? ie ((a,b),c) = (a,(b,c)) = (a, b, c)
a|(b|c) = (a|b)|c = a|b|c
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Sum types: Typescript, Flow, Ceylon, Dotty
Product types: Not sure - afaik, Idris, Agda, and Lean's sum types associate to the right only
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I dunno, associative sums would be kind of hard to work with if they were positional only. Row polymorphism + union operator could work.
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woops: s/sums/products/
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Positional, as opposed to path navigation, like caaddr cdaddr silliness in Lisp?
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Positional in terms of tuples vs records
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Same as usual way with n-tuples? Pattern matching, _1, _2, etc.
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I think the mistake is seeing `(,)` as an operator. in fact they are a whole bunch of hard-wired data constructors: `(,)`, `(,,)`, `(,,,)`…
Bleh, I mean 'type' constructors - confusing because Haskell overloads types and values :P
Think you *might* be forced to add a subtyping relation at some stage to the type system in order to get it to work. Could be wrong though.
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