cpp/experimental/ranges/concepts/WeaklyEqualityComparableWith

The concept specifies that an object of type  and an object of type  can be compared for equality with each other (in either order) using both  and, and the results of the comparisons are consistent. More formally, is satisfied only if given the following are true:
 * , an lvalue of type and
 * , an lvalue of type ,
 * ,, , have the same domain;
 * ; and
 * ; and