On 7/17/2020 7:23 AM, emmanuel.coirier@caissedesdepots.fr wrote:
Hello everyone,
I'm sorry if my proposition has already being said, or even withdrawn, but I think that capture variables shouldn't be as implicit as they are now.
I've looked at the PEP very quickly, jumping on the examples to have a taste and an idea of what was going here. I saw a new kind of control structure based on structural pattern matching (pattern based on classes or compositions of classes to make it short). A very good idea, emphasized by Tobias Kohn ("Another take on PEP 622") is that pattern matching eases the writting of code based on matching such structures, and that capturing values stored inside of these structures at the match time really eases the writting of the code associated with this match.
A major points of Kohn's post is that 'case' is analogous to 'def' and match lists are analogous to parameter lists. In parameter lists, untagged simple names ('parameter names') are binding targets. Therefore, untagged simple names in match lists, let us call them 'match names' should be also. I elaborated on this in my response to Tobias. -- Terry Jan Reedy