empty charset registry?

[Aidan Kehoe]

 Ar an seacht? l? de m? na Samhain, scr?obh Ilya N. Golubev: 

 > Your 2006-11-05 change of how font is searched for given mule charset
 > when instancing font specifiers is clearly user visible.  Still there
 > is no documentation changes reflecting that, let alone addition to
 > `NEWS'.  One of incompatibilities is that currently the call:
 > 
 > (set-charset-registry 'ascii "")
 > 
 > signals error:
 > 
 > (invalid-argument "Not an X11 REGISTRY-ENCODING combination" "")
 > 
 > 
 > Before the change doing this particular elisp call had an obvious and
 > a very useful effect.  That is, user could easily view raw text
 > without explicit mule decoding. 

?C?mo? 

Of course there is Mule decoding, otherwise the characters would be
displayed as numbers. 

 > This is extremely valueable when viewing data items consisting of
 > snippets of text in different 8-bit encodings.  Those easily result from
 > erroneous process output, or simply are some legacy text files.  This was
 > possible because could obviously specify xemacs to display raw text
 > charsets in the very first font retrieved from font specifier for
 > particular locale, like this.
 > 
 > (let ((l '(ascii latin-iso8859-1)))
 >   (while l
 >     (set-charset-registry (car l) "")
 >     (setq l (cdr l))))
 > 
 > Then would just set font specifications in default (or even perhaps
 > other) face font specifiers for frame (or window), and could rely
 > xemacs to display raw text in exactly the font as specified.

That?s a horrible, evil hack. 

 > Another incompatibility is that `control-1' characters are always
 > displayed as `\OCTAL', not as code points of some 8-bit font.  The
 > latter may be disired for the same reasons.
 > 
 > How do we view raw text in user specified font after the change? 

(set-charset-registry 'ascii "charset-registry-of-desired-font")
(set-charset-registry 'latin-iso8859-1 "charset-registry-of-desired-font")
(set-face-font 'default "full-xlfd-of-desired-font")

That is to say, work out which font you want, and choose it. 

 > How do we check whether `set-charset-registry' in given version and build
 > implements old or new data format?  Please document.

You shouldn?t need to, if you use the above two lines. 

-- 
Santa Maradona, priez pour moi!