Template Haskell Extension TyFamInstD?

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#1

What does the GHC AST type TyFamInstD correspond to in TH?

Given,

class X a where
    type Z a

instance X A where
    type Z A = ...                         <- this

Thanks!

#2

It looks like TySynInstD:

Prelude> :set -XTemplateHaskell
Prelude> :set -XTypeFamilies 
Prelude> class X a where type R a
Prelude> x = [d| { instance X Int where type R Int = Bool } |]
Prelude> import Language.Haskell.TH.Syntax
Prelude Language.Haskell.TH.Syntax> runQ x
[InstanceD Nothing [] (AppT (ConT Ghci1.X) (ConT GHC.Types.Int)) [TySynInstD (TySynEqn Nothing (AppT (ConT Ghci1.R) (ConT GHC.Types.Int)) (ConT GHC.Types.Bool))]]
Prelude Language.Haskell.TH.Syntax>
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#3

Hah. I completely forgot about GHCi! Thanks!