[Python-ideas] Operator as first class citizens -- like in scala -- or yet another new operator?

[Yanghao Hua]

On Wed, May 29, 2019 at 3:45 AM Greg Ewing <greg.ewing at canterbury.ac.nz> wrote:
>
> Yanghao Hua wrote:
> > a different assignment behavior in HDL is your assignment does not
> > take effect until a delta cycle of zero virtual time has passed. (did
> > you really looked at the previous postings? :)
>
> You need to understand that most of the people reading this are not
> familiar with the workings and semantics of HDLs, so that phrases
> like "delta cycle of zero virtual time" are meaningless word salad.
> We need you to tell us what this new kind of assignment will do
> in *Python* terms.

It should do nothing in python terms, but rather let the user decide
what to do. This is for representing ideas for a specific domain, if I
explain in HDL terms, people complain python people cannot make sense
out of it, if I explain in Python terms, people complain what problem
are you trying to solve? So ... the short answer is this is the last
thing python lacks of flexibility and would be great if python
community are interested to support it.

> > x = 4 should be something like x <== 4 or x := 4 (the latter has been
> > taken by the assignment expressions though ...). Such that variable
> > initialization (=) and utilization (<==) can be differentiated.
>
> Since you seem to be willing to use a different syntax for this
> kind of assignment, my suggestion is something like
>
>     x = Signal()
>     ...
>     x.next = 4
>
> If I understand correctly what you want to use this for, that
> would be both suggestive of the semantics and entirely doable
> with existing Python features.

Yes sure this is doable, and this is exactly how I am doing it with
python to interface verilog, e.g. signals are always accessed through
module instances, and this is perfectly fine for verification. And
there is another dozen different way to do this. But this is just not
as intuitive as x <== 4 I am afraid. And for me this just kills all my
motivation to use python to design hardware. If I use python to do
something and I have to type more chars it doesn't make sense for me.