Matsuoka Takuo <motogeom...@gmail.com>: > > Now, is "1,2," more boxed up than "*(1,2)," is? The *current* rule > surely says the former is a tuple at some places and the latter > is not,
Actually, this was wrong. First of all, >>> *(1,2), (1, 2) Moreover, while the Language Reference says return_stmt ::= "return" [expression_list] at https://docs.python.org/3/reference/simple_stmts.html#the-return-statement things like return *(), are already allowed and () gets returned in this case, and so on! I haven't examined everything, but so far, subscription is the only place I've found where a starred expression in place of an expression list indeed raises SyntaxError. In particular, there really doesn't seem to be any reason why a starred expression should be rejected from any place where an expression list is accepted. In fact, rejection should _not_ be expected, it seems. My proposal at this point would be: (1) remove the definition of "expression_list" from the specification of the syntax (2) replace every occurrence of it in the specification with "starred_expression". At most places this seems to only recover the current behaviour. (Even if this idea does not survive in the end, I think the Language Reference should be fixed to describe the behaviour correctly. The actual behaviour is making better sense to me than what the Reference is describing now.) A minor question to be left then would be which new instance of "starred_expression" in the specification of the syntax may further be replaced with the optional one or "[starred_expression]", e.g., whether s[] would be better allowed and evaluated to s.__getitem__(()). This may be complicated. For example, I'm already used to returning None with return and so on. Even then, s[] doesn't seem very bad to me. Best regards, Takuo _______________________________________________ Python-ideas mailing list -- python-ideas@python.org To unsubscribe send an email to python-ideas-le...@python.org https://mail.python.org/mailman3/lists/python-ideas.python.org/ Message archived at https://mail.python.org/archives/list/python-ideas@python.org/message/6CKPSNDUPMA2HMX2I25ECFEQ4F4CD2XB/ Code of Conduct: http://python.org/psf/codeofconduct/
