Re: Type Properties for Templates
On Apr 27, 2:48 am, Andrew Tomazos <and...@tomazos.com> wrote:
Is it possible with existing C++ language features to declare a type
as having a certain property and then (a) making a static assertion
that a type parameter has this property, and/or (b) specializing a
template for types that have this property.
template<class T, class P> struct has_property : boost::mpl::false_
{};
struct property_x;
class Foo;
template<> struct has_property<int, property_x> : boost::mpl::true_
{};
template<> struct has_property<Foo, property_x> : boost::mpl::true_
{};
template<class T>
void f()
{
BOOST_MPL_ASSERT((has_property<T, property_x>));
}
template<class T, class Enabler = void> class C;
template<class T>
class C<T, typename boost::enable_if<has_property<T,
property_x>::type>
{
...
};
template<class T>
class C<T, typename boost::disable_if<has_property<T,
property_x>::type>
{
...
};
Yechezkel Mett
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