Re: char-table-range

[Luc Teirlinck <teirllm@dms.auburn.edu>]

Ken'ichi Handa wrote:

   Luc pointed out the current odd behaviour of
   char-table-range.  What should we do if values of characters
   in the specified range are different?

Maybe it should be clarified that this was pointed out in private
email while discussing a fix to another bug (so people do not start
searching the archives for a non-existing report).

The current behavior for ascii and eight-bit-{graphic,contol} is so
odd that it probably can be safely called a bug.  Note that in the
ielm run below (char-table-range cc 'ascii) actually returns the value
specified for eight-bit-control.  For other charsets (I took ipa as
example), things would seem to be OK.

My own opinion would be to have char-table-range return the default
value, except for ascii and eight-bit-{control,graphic} which do not
have a default value.  For those it would seem to me that the best
thing to do would be to throw an error.

===File ~/char-table-ielm===================================
*** Welcome to IELM ***  Type (describe-mode) for help.
ELISP> (put 'five-slots 'char-table-extra-slots 5)
5
ELISP> (setq cc (make-char-table 'five-slots))
;; long output deleted.
ELISP> (set-char-table-range cc 'ascii 1)
1
ELISP> (set-char-table-range cc 'eight-bit-control 2)
2
ELISP> (set-char-table-range cc 'eight-bit-graphic 3)
3
ELISP> (set-char-table-range cc 'ipa 4)
4
ELISP> (char-table-range cc 'ascii)
2
ELISP> (char-table-range cc 'eight-bit-graphic)
nil
ELISP> (char-table-range cc 'eight-bit-control)
nil
ELISP> (char-table-range cc 'ipa)
4
ELISP> 
============================================================