Message 337869 - Python tracker

Message337869

Author	tim.peters
Recipients	arigo, brandtbucher, pablogsal, rhettinger, serhiy.storchaka, tim.peters
Date	2019-03-13.18:51:18
SpamBayes Score	-1.0
Marked as misclassified	Yes
Message-id	<1552503079.05.0.799624485797.issue36229@roundup.psfhosted.org>
In-reply-to

Content
Serhiy, if I understand this, it _could_ pay big with even just a few operations. For example, [0] * 1000000 + [1] + [2] + [3] As-is, we'll copy the million zeroes three times. WIth the patch, more likely the original vector of a million zeroes would be extended in-place, three times with a single element each time. But I don't know that people do that in real code. It would be great to find real examples in real could that would benefit.

Content

Serhiy, if I understand this, it _could_ pay big with even just a few operations.  For example,

    [0] * 1000000 + [1] + [2] + [3]
    
As-is, we'll copy the million zeroes three times.  WIth the patch, more likely the original vector of a million zeroes would be extended in-place, three times with a single element each time.

But I don't know that people do that in real code.  It would be great to find real examples in real could that would benefit.

History
Date	User	Action	Args
2019-03-13 18:51:19	tim.peters	set	recipients: + tim.peters, arigo, rhettinger, serhiy.storchaka, pablogsal, brandtbucher
2019-03-13 18:51:19	tim.peters	set	messageid: <1552503079.05.0.799624485797.issue36229@roundup.psfhosted.org>
2019-03-13 18:51:19	tim.peters	link	issue36229 messages
2019-03-13 18:51:18	tim.peters	create