On Sun, May 26, 2019 at 6:05 AM Terry Reedy <tjre...@udel.edu> wrote: > > 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.
Yes you are right. @ is not a number operation, it is number-collection operation. What is preventing the same operation on signal-collections? > > I admit this (@=) is a much rarer case, > > It is a different case. Really not much different for me as you can use it to operate on matrix (which can be either a matrix of number or matrix of signals). > > 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. I really don't understand the argument here. And let's apply the same argument to PEP465 why not matrix multiply override <<= instead? For me not using @= is exactly the same reason for not using <<= and others. > 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. I think people don't get confused by a + b because a + b does mean a + b and does not mean a * b and it has nothing to do with how you name the operands. _______________________________________________ Python-ideas mailing list Python-ideas@python.org https://mail.python.org/mailman/listinfo/python-ideas Code of Conduct: http://python.org/psf/codeofconduct/
