C++0x Concepts - Dead?

[Walter Bright]

Christian Kamm wrote:
> BLS Wrote:
>> I have somehow the idea that D constraints and template specialization 
>> should merge.
> 
> I also feel that specialization may just be a special case of constraints -
> with the added benefit that implicit function template instantiation works.
> 
> Is there a difference between
> template Foo(T : U) {} and 
> template Foo(T) if(is(T : U)) {} ?
> 

Yes. Constraints determine the list of candidate template declarations, 
but do not participate in the partial ordering of candidates to 
determine the 'best' match.