Re: [Boost-users] [parameter] Parameter-Enabled Class Templates:combining keyword and deduction for the same parameter

From: Daniel Wallin (daniel_at_[hidden])
Date: 2007-07-19 17:58:16

David Abrahams wrote:
> on Thu Jul 19 2007, "JOAQUIN LOPEZ MU?Z" <joaquin-AT-tid.es> wrote:
> 
>> Just to be sure: so, given the parameter specification
>>
>>   required<deduced<tag::T>,F>,
>>
>> Boost.Parameter matches it to T<X> even if X does *not* satisfy
>> F, correct?
> 
> That's the intention... although I can't promise SFINAE won't kick in
> in some cases.

Joaquin was talking about class templates, so the above holds true.
SFINAE will kick in if you use the restriction mechanism for function
templates. The PP interface does that, so if you use that you can't
supply parameter types that doesn't match the predicate.

-- 
Daniel Wallin
Boost Consulting
www.boost-consulting.com