Re: GADT record syntax and contexts

Simon Peyton-Jones wrote:

(A) data RecContTest a where Show a => C { showable :: Show a => a } :: RecContTest a

(B) data RecContTest a where C :: Show a => { showable :: Show a => a } -> RecContTest a

What about (A') data RecContTest a where Show a => C { showable :: a } :: RecContTest a (B') data RecContTest a where C :: Show a => { showable :: a } -> RecContTest a ? Would this be allowed? I would expect A' and B' to generate showable :: RecContTest a -> a and not the less useful (Show-requiring) showable :: Show a => RecContTest a -> a Zun.