#6018: Injective type families
------------------------------+---------------------------------------------
Reporter: lunaris | Owner:
Type: feature request | Status: new
Priority: normal | Component: Compiler
Version: 7.4.1 | Keywords: TypeFamilies, Injective
Os: Unknown/Multiple | Architecture: Unknown/Multiple
Failure: None/Unknown | Testcase:
Blockedby: | Blocking:
Related: |
------------------------------+---------------------------------------------
Comment(by lunaris):
Oops -- I forgot to list all that was wrong with the current
implementation. Namely:
* In the example, {{{g}}}'s type is inferred as {{{a -> a}}} (and not
{{{G a -> G a}}}). This is in some sense `correct', but seems a bit dodgy.
* I don't actually *enforce* that the declared instances of a family
*are* injective yet -- I've put that off until what's there is semi-
stable.
* I've messed up and inadvertently included whitespace changes in one of
the patches. Apologies.
--
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/6018#comment:1>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler
_______________________________________________
Glasgow-haskell-bugs mailing list
[email protected]
http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
