all messages for Emacs-related lists mirrored at yhetil.org
 help / color / mirror / code / Atom feed
From: Leo Liu <sdl.web@gmail.com>
To: Andreas Schwab <schwab@linux-m68k.org>
Cc: emacs-devel@gnu.org
Subject: Re: why is reverse a string in-place so much slower than a vector?
Date: Fri, 25 Apr 2014 17:35:58 +0800	[thread overview]
Message-ID: <m3vbtxlpj5.fsf@gmail.com> (raw)
In-Reply-To: <87zjj9n53w.fsf@igel.home> (Andreas Schwab's message of "Fri, 25 Apr 2014 11:14:11 +0200")

On 2014-04-25 11:14 +0200, Andreas Schwab wrote:
> String random access has linear complexity: there is a single element
> cache for the last known char->byte mapping for the last accessed
> string, and the runtime depends on the distance from this point.  Your
> rev function represents the worst case behaviour.

Thanks for this piece of critical information. I guess this is all due
to `string_char_to_byte'?

Leo



  reply	other threads:[~2014-04-25  9:35 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-04-25  8:12 why is reverse a string in-place so much slower than a vector? Leo Liu
2014-04-25  8:17 ` Leo Liu
2014-04-25  8:55   ` Rüdiger Sonderfeld
2014-04-25  9:14   ` Andreas Schwab
2014-04-25  9:35     ` Leo Liu [this message]
2014-04-25 11:00       ` Andreas Schwab
2014-04-26  0:19         ` Leo Liu

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=m3vbtxlpj5.fsf@gmail.com \
    --to=sdl.web@gmail.com \
    --cc=emacs-devel@gnu.org \
    --cc=schwab@linux-m68k.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
Code repositories for project(s) associated with this external index

	https://git.savannah.gnu.org/cgit/emacs.git
	https://git.savannah.gnu.org/cgit/emacs/org-mode.git

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.