Re: Changes to Typeable

On 11 February 2012 00:30, John Meacham wrote:

Would it be useful to make 'Proxy' an unboxed type itself? so

Proxy :: forall k . k -> #

This would statically ensure that no one accidentally passes ⊥ as a parameter or will get anything other than the unit 'Proxy' when trying to evaluate it. So the compiler can unconditionally elide the parameter at runtime. Pretty much exactly how State# gets dropped which has almost the same definition.

Or don't use an argument at all: class Typeable t where typeRep :: Tagged t TypeRep newtype Tagged s b = Tagged { unTagged :: b } See: http://hackage.haskell.org/packages/archive/tagged/0.2.3.1/doc/html/Data-Tag... Bas