Re: [Bug-AUCTeX] 11.84; Font replacing doesn't work for unbalanced parentheses.

[Ikumi Keita]

>>>>> Ralf Angeli writes:

> That's a bug in Emacs 21 which is fixed in CVS Emacs.  (See the
> comment in the defvar of `TeX-syntax-table'.)  As a workaround we
> could set the syntax entries for parens to nil.

I see.  Sorry for my lack of knowledge about CVS Emacs.

> The variable is not supposed to be used directly.  If a syntax table
> for searching is required, the function `TeX-search-syntax-table'
> should be used.  Working with only a single syntax was a deliberate
> decision because syntax tables are quite large data structures and I
> didn't want to waste memory by making that variable buffer-local or do
> something similar.

Sorry, I didn't give an example concrete enough.  Here is the detail.

1. Assume that the buffer foo is in texinfo-mode and the buffer bar is
   in latex-mode.
2. Go to the buffer foo and type C-c C-f C-e.
3. As expected, @emph{} is inserted.
4. Place the cursor on @emph and type C-u C-c C-f C-e.
5. At this point,

(char-to-string (with-syntax-table (TeX-search-syntax-table ?{ ?}) (char-syntax 
?@)))

   returns "\\".  This is OK.
6. Go to the buffer bar.
7. Evaluating

(char-to-string (with-syntax-table (TeX-search-syntax-table ?{ ?}) (char-syntax 
?@)))

   gives "\\", which is unwanted.  The char `@' should not have escape
   syntax in latex-mode buffer.

The item 7 is what I tried to point out in the paragraph
>> In addition, the way the function TeX-search-syntax-table treats the
>> variable TeX-search-syntax-table does not seem good to me.  The function
>> directly modifies the syntax table stored in the variable, so the
>> modified table is shared between all the buffers.  For examle, the char
>> `@' is given escape syntax in texinfo-mode buffer, which should be
>> avoided in latex-mode buffer.

In other words, the function TeX-search-syntax-table should initialize
the variable every time if a single syntax table is to be shared between
all the buffers of dirrerent modes.

Regards,
----
Ikumi Keita