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

[Terry Reedy]

On 5/25/2019 3:09 PM, Yanghao Hua wrote:

> @= has all the same issues like <<= or >>=,

No, it does not

> in that you are basically
> sacrificing a well known number operation

because @= is not a number operation at all.

> I admit this (@=) is a much rarer case,

It is a different case.

> but why do we want to exclude
> the possibility for a matrix of signals to multiply another matrix of
> signals and assign the result to another matrix of signals?

We do not.  <int subclass instance> @= int would be implemented by the 
__imatmul__ method of the int subclass.  matrix @= matrix is implemented 
by the __imatmul__ method of the matrix class.  This is similar to 1 + 2 
and [1]  + [2] being implemented by the __add__ methods of int and list 
respectively.

  how does
> this look like? X @= (X @ Y), where @= means signal assignment, and X
> @= Y, does it mean signal assignment of Y to X, or does it mean X = X
> @ Y? This simply causes a lot of confusions.

Why don't people more often get confused by a + b?  Partly because they 
use longer-that-one-char names that suggest the class.  Partly because 
they know what a function is doing, perhaps from a name like 
set_signals.  Party because they read the definitions of names. 
Conventionally in math, scalars values are lower case and matrices are 
upper case.  So x*y and X * Y are not confused.

-- 
Terry Jan Reedy