bug#5799: 24.0.50; Case and search problems in unibyte buffers

bug#5799: 24.0.50; Case and search problems in unibyte buffers

[bojohan]

http://lists.gnu.org/archive/html/help-gnu-emacs/2010-03/msg00246.html


This correctly finds a \377 character in a unibyte buffer:

    (let ((case-fold-search nil)) (search-forward "\377"))

This fails to match \377 and actually finds \277 instead:

    (let ((case-fold-search t)) (search-forward "\377"))


`downcase' behaves strangely too:

    (let ((default-enable-multibyte-characters nil))
      (with-temp-buffer
        (downcase 255)))
    => 4194303

These problems exist in trunk and Emacs 23, and did not occur in
Emacs 22.

bug#5799: 24.0.50; Case and search problems in unibyte buffers

[Eli Zaretskii]

> From: bojohan@gnu.org
> Date: Mon, 29 Mar 2010 22:48:08 +0200
> Cc: 
> 
> `downcase' behaves strangely too:
> 
>     (let ((default-enable-multibyte-characters nil))
>       (with-temp-buffer
>         (downcase 255)))
>     => 4194303

This part is by design, I think: see the node "Character Codes" in the
ELisp manual.  4194303 is the internal multibyte representation of the
raw byte 255, part of the eight-bit charset.

bug#5799: 24.0.50; Case and search problems in unibyte buffers

[Lars Magne Ingebrigtsen]

bojohan@gnu.org writes:

> http://lists.gnu.org/archive/html/help-gnu-emacs/2010-03/msg00246.html
>
> This correctly finds a \377 character in a unibyte buffer:
>
>     (let ((case-fold-search nil)) (search-forward "\377"))
>
> This fails to match \377 and actually finds \277 instead:
>
>     (let ((case-fold-search t)) (search-forward "\377"))

I'm no longer able to reproduce this bug, so I think it was fixed by
Andreas' recent fixes in this area.

-- 
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  bloggy blog http://lars.ingebrigtsen.no/