Steven D'Aprano wrote:
Yanghao Hua wants to customise the behaviour of assignment. I believe that he wants to emulate the behaviour of some hardware description languages, where the equals sign = doesn't mean assignment (if I have understood correctly, which I may not have), but Something Else.
Maybe I can help a bit here. I don't have a deep knowledge of HDLs. but from what I gather, they typically have two different assignment-like operations. One of them is like assignment in a functional language, where you're defining a signal as a function of other existing signals. This corresponds to combinatorial logic in hardware. Python's existing assigment is fine for this, I think.
The other represents updating a signal when some event occurs, such as a clock transition. In hardware terms, it corresponds to changing the state of a flip-flop. The OP wants a new operator and associated dunder method to represent this operation. He doesn't want to override normal assignment.