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[Monotone-devel] Re: using empty() instead of size()
From: |
Bruce Stephens |
Subject: |
[Monotone-devel] Re: using empty() instead of size() |
Date: |
Mon, 22 Sep 2008 23:04:27 +0100 |
User-agent: |
Gnus/5.11 (Gnus v5.11) Emacs/22.2 (gnu/linux) |
Markus Wanner <address@hidden> writes:
> Zack Weinberg wrote:
>> Sure, but C++98 requires size() to be O(1) for every container, so
>> there's really no excuse for a 4-15% performance difference.
>
> Hm.. I didn't know that, thanks.
Just because the standard says that doesn't mean that it's so in
implementations, of course. For example size() in SGI's list may be
linear: <http://www.sgi.com/tech/stl/List.html>.
The standard uses odd terminology (I think, anyway). There's a table
in 23.1 showing the operations and complexities, and some of the
complexities are "constant", and some are "(Note A)". This is
explained below the table: "Those entries marked ‘‘(Note A)’’ should
have constant complexity."
I wonder if that's an RFC-style "should"?
I don't have a more recent standard---perhaps this has changed?
- [Monotone-devel] using empty() instead of size(), Markus Wanner, 2008/09/22
- Re: [Monotone-devel] using empty() instead of size(), Zack Weinberg, 2008/09/22
- Re: [Monotone-devel] using empty() instead of size(), Markus Wanner, 2008/09/22
- Re: [Monotone-devel] using empty() instead of size(), Jens Finkhäuser, 2008/09/22
- Re: [Monotone-devel] using empty() instead of size(), Zack Weinberg, 2008/09/22
- Re: [Monotone-devel] using empty() instead of size(), Markus Wanner, 2008/09/22
- [Monotone-devel] Re: using empty() instead of size(),
Bruce Stephens <=
- Re: [Monotone-devel] Re: using empty() instead of size(), Zack Weinberg, 2008/09/22
- [Monotone-devel] Re: Re: using empty() instead of size(), Boris, 2008/09/23
- Re: [Monotone-devel] using empty() instead of size(), Markus Wanner, 2008/09/22
- Re: [Monotone-devel] using empty() instead of size(), Zack Weinberg, 2008/09/22
- Re: [Monotone-devel] using empty() instead of size(), Derek Scherger, 2008/09/22
- [Monotone-devel] Re: using empty() instead of size(), Bruce Stephens, 2008/09/23
- Re: [Monotone-devel] Re: using empty() instead of size(), Ulf Ochsenfahrt, 2008/09/23
- Re: [Monotone-devel] Re: using empty() instead of size(), Bruce Stephens, 2008/09/23
- Re: [Monotone-devel] Re: using empty() instead of size(), Ulf Ochsenfahrt, 2008/09/23
- [Monotone-devel] Re: using empty() instead of size(), Bruce Stephens, 2008/09/23