On Mon, 2008-03-31 at 00:09 -0700, Eric Niebler wrote:
Giovanni Piero Deretta wrote:
On Fri, Mar 28, 2008 at 9:56 PM, Eric Niebler <eric@boost-consulting.com> wrote: What about
template<class Wrapped<typename T...>, typename ArgList... > class bind;
bind<vector, foo(bar(_1)), _2>
That should work, even if 'Wrapped' requires it template arguments to conform to some exotic concept.
Really? It seems to me that this would effectively strip the requirements from a template, violating the metatype system. Can someone who knows, comment?
This won't be the case... it doesn't actually strip the requirements from the template, it just defines an unconstrained template and delays the construction of the vector<> until we have something that should meet vector's requirements.
Or may be something like this:
bind<vector>(foo(bar(_1)), _2)
Untested of course, and I'm not sure how concepts interact with template template parameters.
Me neither. Doug? The question is whether this should compile in C++0x:
// Takes an unconstrained template: template<template<typename T> class S> struct foo {};
// A constrained template template<Regular Value> struct vector {};
foo<vector> f; // OK? Prolly not.
Yes, this is well-formed C++0x. We (have to) let unconstrained template template parameters bind to constrained templates. - Doug