On 02/15/2013 03:52 AM, Simon Peyton-Jones wrote:
| Does this mean that if OverloadedLists is on and more than one fromList
| or toList is in scope (even if one of them is GHC.Exts.fromList/toList),
| then list literals and patterns (resp.) will not compile?

No... the documentation is poor on that point:

* Normally, it'll use GHC.Exts.fromList (etc) regardless of
   whether GHC.Exts is imported, or what other fromList's are in scope.

* If you also use -XRebindableSyntax, it'll use whatever fromList is in scope.
   Then if you imported Data.Map and GHC.Exts it'd be ambiguous.

This is precisely the behaviour of, say integer literals.  Normally they 
desugar to a call of the Prelude's fromInteger, but with RebindableSyntax it 
becomes whatever fromInteger is in scope.

I'll fix the documentation.

Simon

Ah, that's what I'd expect.  Thanks!

-Isaac



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