Dfc optimization

[Aidan Kehoe]

 Ar an seachtú lá déag de mí na Samhain, scríobh Stephen J. Turnbull: 

 > >>>>> "Aidan" == Aidan Kehoe <kehoea at parhasard.net> writes:
 > 
 >     Aidan> If mswindows-multibyte may involve the EBCDIC code pages, then
 >     Aidan> it's probably not true.
 > 
 > Doesn't matter, unless mswindows-multibyte starts in one of them, or
 > there's a way to switch out of ASCII using only the printing
 > characters.  

EBCDIC encodes the same characters as, and is incompatible with, ASCII. So
if an some coding system uses it at all, it's unlikely that it uses ASCII. 

But, again, let me go home and look this up. 

 > The precondition is that the stream contains _only_ printing ASCII (I
 > assume that actually the usual whitespace characters are allowed).

Printing ASCII codes or printing ASCII characters? 

(encode-coding-string "éêëè" 'ebcdic)
"QRST"

(Yeah, I wrote an EBCDIC coding system in CCL. I've a patch for the CCL docs
at home that describes the implementation of a URL coding system, and it's
pretty readable and understandable IMHO. If CCL isn't definitively
deprecated--and I don't think it should be--integrating

http://lists.gnu.org/archive/html/gnu-emacs-sources/2002-04/msg00013.html

will be worth doing.)

 > Doesn't matter, because we don't support them as part of any of the
 > encodings Ben mentioned.  The optimization would not be supported for
 > them, obviously.

Sure. 

-- 
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their successors, his have been disappointed--once more, the world has shown
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