Should we add `a * b` for vectors?

[Timon Gehr]

On 06.10.2017 00:04, Jonathan M Davis wrote:
>>
>>
>> I'm very much in favor of this. Also, those rewrites should be
>> consistently applied for all types, even built-ins (the compiler
>> implementation can be more complex, but the language rules would be
>> simplified).
>> One immediate benefit would be that opCmp could be reliably used for all
>> types that support comparison, for example 2.opCmp(3).
>> Another benefit would be that operators such as += can reassign class
>> references, for example when a value type is implemented as a unique
>> reference to immutable data.
> Being able to do 2.opCmp(3) would be pretty cool, but I'm still convinced
> that allowing for operators to be overloaded outside of the type is a
> terrible idea. It's far cleaner for them to be tied to the type

It's far from clean because it enforces a certain calling convention.

> - especially
> when you consider that it's not possible to differentiate between
> conflicting overloadeded operators.

This is just not true. D has enough mechanisms for differentiating 
between conflicting overloads.

> And having them declared outside of the
> type just opens up all of the problems that were just being complained about
> in this thread with templated code not being able to access free functions
> that weren't imported in the module that it's in.

Those are UFCS issues, but I'd rather have UFCS than no UFCS.