is_swappable

Header

#include <tick/traits/is_swappable.h>

Description

Checks if type T can be called with either std::swap or an ADL overload of swap.

Requirements

Type U is swappable with type T if, for any object u of type U and any object t of type T

Expression	Requirements
using std::swap; swap(t, u);	After the call, the value of t is the value held by u before the call, and the value of u is the value held by t before the call.
using std::swap; swap(u, t);	After the call, the value of t is the value held by u before the call, and the value of u is the value held by t before the call.

Synopsis

TICK_TRAIT(is_swappable)
{
    using std::swap;
    template<class T>
    auto require(T&& x) -> valid<
        decltype(swap(x, x))
    >;

    template<class T, class U>
    auto require(T&& x, U&& y) -> valid<
        decltype(swap(x, y))
        decltype(swap(y, x))
    >;
};