Re: [boost] [concept_check] Problem with concept checks and overloads

From: Bruno Lalande (bruno.lalande_at_[hidden])
Date: 2008-07-23 19:26:12

Hi Luke,

I'm not sure your problem is the same as mine. My problem is that the
result type gets compiled even though there's absolutely no ambiguity
between the 2 functions. There's no need to do any SFINAE
discrimination to conclude that foo<T>& matches much better that T&
for this call. I'd be happy if the compiler waited to have a true
ambiguity to solve before compiling any return type but things are
like that, I can't rewrite the norm.

Your problem is rather a lack of strength of SFINAE. As you say, the
SFINAE principle seems to be only applied on a first-level check. If
the substitution fails at a more nested level, it's an error. To be
honest, this surprises me. Don't know what the norm says about that...

Thanks John to have retried your test, I feel less alone now :-)

Bruno