Constraints on Type Constructors

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,
#1

Hi,
I’m trying to use Type Constraints on a type constructor in a forall

    data Action = 
      Inc 
      | Dec 
      | MakeEditable (forall a b r1. Lacks a r1 => Cons a b r1 PersonRow => SProxy a) 
      | ChangeCurrent (forall l b r1. IsSymbol l => Lacks l r1 => Cons l b r1 PersonRow => Tuple b (SProxy l))

where PersonRow is a Row. When I try to pattern match on ChangeCurrent i get cannot match constrained type. Also when I try to make the type incorrectly. like say (ChangeCurrent (Tuple 1 2)) where 2 isnt even a symbol. i dont get any errors but when i try and when i pattern match i do?

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#2
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