Bob Steagall

Hi Mat and Mark. I'll have to think about this. At first glance Mark's diagonal matrix idea seems plausible. However, one barrier is the underlying assumption in the design that...

Mark, I agree. One can imagine a kind of "shadow matrix" that carries the extra type information (beyond unitless element type, that is).

This is on the schedule to be added to R7.

Thanks for finding this. I haven't built RPMs in a while. I'll see that it gets fixed.

What is the offending code that caused the failure? That static assert is there for a reason -- if it fires, then the dimensions of the multiplication don't line up,...

I need some example code to test against.

Yes, but overload resolution is not the source of the `static_assert` failing in your Godbolt example; the definition of `foo(double)` is. Comment out the call to `foo` in `main` and...

Note that I am not disagreeing with your statements about using concepts -vs- static assert. I am however trying to understand the source of the `static_assert` failure.

> As I said, I strongly suspect that it’s a decltype usage (not an actual call, see the error output) in @mpusz’s code and the usage of an auto return...

In fact, as I look at the error messages, it appears to be an attempt to multiply a 3x1 matrix by a 3x1 matrix, which _is_ incompatible.