Re: [PATCH] Unicode Lisp reader escapes

[Aidan Kehoe]

 Ar an dara lá de mí Bealtaine, scríobh Eli Zaretskii: 

 > Whether it is safe or not, I think it's certainly better to implement
 > the guts of decode-char in C, if it's gonna be called from
 > read_escape. 

If it’s only going to be called rarely (twice a file for non-byte-compiled
files, at a liberal guess, never for byte-compiled files), and after
decode-char is already loaded--both of which are the case--I don’t see the
argument for that.

 > All those guts do is simple arithmetics, which will be much faster in C.
 >
 > Moreover, I think the fact that decode-char uses translation tables to
 > support unify-8859-on-*coding-mode (and thus might produce characters
 > other than mule-unicode-*) could even be a misfeature: do we really
 > want read_escape to produce Unicode or non-Unicode characters when it
 > sees \uNNNN, depending on the current user settings?

This is not significantly different from the question “do we really want
(decode-char 'ucs #xABCD) to produce Unicode or non-Unicode characters
depending on the current user settings?”, since making string escapes
inconsistent with the Unicode coding systems does not make any sense. And
that question has already been answered. Cf. 
http://article.gmane.org/gmane.emacs.bugs/3422 . 

-- 
Aidan Kehoe, http://www.parhasard.net/