Wildcard type annotations

Andres Loeh loeh at iai.uni-bonn.de
Mon Jan 23 19:39:43 EST 2006

> note that this is subsumed by my existential type synonyms proposal
> type Any = exists a . a
> so Any is any type.
> at least, I think that works. I didn't get a whole lot of feedback on
> the proposal.

I haven't looked at your proposal yet, but existential types are not
the same as partial type signatures.

> x :: Any
> x = 2

Here, "x" would be essentially unusable, i.e., only applicable to polymorphic

> x :: _
> x = 2

The above, however, would be the same as giving no type signature for "x"
at all ...


More information about the Haskell-prime mailing list