On Tuesday, 12 January 2016 at 20:56:41 UTC, John Colvin wrote:
Please consider the second design I proposed? It's small,
simple, has no impact on existing code and works in the right
direction (library types can emulate / act as replacements for
builtins) as opposed to the other way (library types are second
class).
If non-total ordering is going to be supported, I don't
understand what's wrong with just allowing this:
bool opCmp(string op, T)(T right) const { }
As an alternative to the current:
bool opEquals(T)(T right) const { }
int opCmp(T)(T right) const { }
Make it a compile-time error for a type to implement both. There
is no need to deprecate the current system - people can even be
encouraged to continue using it, in the very common case where it
can actually express the desired logic.
This approach is simple and breaks no existing code. It is also
optimally efficient with respect to runtime performance.
