Should we add `a * b` for vectors?

[jmh530]

On Wednesday, 27 September 2017 at 23:25:34 UTC, Manu wrote:
>
> Again, sadly, D has no ADL, and this will be an unmitigated 
> disaster as a
> result!
> Instantiations of templates will use the default elementwise 
> operator
> instead of the one you specified in your module, and nobody 
> will understand
> why.

Argument-dependent lookup? I'm not an expert on C++, but I read 
the wikipedia entry on it. It does seem like an issue worth 
thinking more about

One (hacky) solution is to not have default implementations for 
the all the operators (the focus so far has been on the multiple 
uses of * for element-wise multiply and dot product/matrix 
multiplication). So you have Slice in mir.ndslice.slice. Then 
make a mir.ndslice.operator.elementwise module that has the 
operator overloading for elementwise operations, then a module 
mir.ndslice.operator.linalg (or somewhere in lubeck) with the dot 
product or inverse implementations. The key to making this work 
is that you also need a mid.ndslice.arithmetic or something that 
allows the user to call these functions without operator 
overloading. This way they can put import their default, but if 
they have a function that mixes and matches dot and element-wise 
multiplication, they can do that too.