Message 306198 - Python tracker

Message306198

Author	ncoghlan
Recipients	benjamin.peterson, brett.cannon, cryvate, gvanrossum, ncoghlan, serhiy.storchaka, yselivanov
Date	2017-11-14.10:28:28
SpamBayes Score	-1.0
Marked as misclassified	Yes
Message-id	<1510655308.25.0.213398074469.issue32012@psf.upfronthosting.co.za>
In-reply-to

Content
I created https://bugs.python.org/issue32023 to explicitly cover the base class list case, and after checking the language spec, I agree that case should be a syntax error. However, `@deco(x for x in [])` should not be a syntax error, as: * it's a call with one argument, so the genexp parentheses can be omitted as described in https://docs.python.org/3/reference/expressions.html#generator-expressions * it matches the "@dotted_name(arg_list)" pattern permitted by https://docs.python.org/3/reference/compound_stmts.html#function-definitions

Content

I created https://bugs.python.org/issue32023 to explicitly cover the base class list case, and after checking the language spec, I agree that case should be a syntax error.

However, `@deco(x for x in [])` should *not* be a syntax error, as:

* it's a call with one argument, so the genexp parentheses can be omitted as described in https://docs.python.org/3/reference/expressions.html#generator-expressions
* it matches the "@dotted_name(arg_list)" pattern permitted by https://docs.python.org/3/reference/compound_stmts.html#function-definitions

History
Date	User	Action	Args
2017-11-14 10:28:28	ncoghlan	set	recipients: + ncoghlan, gvanrossum, brett.cannon, benjamin.peterson, serhiy.storchaka, yselivanov, cryvate
2017-11-14 10:28:28	ncoghlan	set	messageid: <1510655308.25.0.213398074469.issue32012@psf.upfronthosting.co.za>
2017-11-14 10:28:28	ncoghlan	link	issue32012 messages
2017-11-14 10:28:28	ncoghlan	create