char-table-range

[Kenichi Handa <handa@m17n.org>]

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?

For the moment, I don't have a good idea.  Possible
behaviours are:

(1) return nil
(2) return the first non-nil value in the range.
(3) return the default value of the range (but ascii,
    eight-bit-XXXX doesn't have a default value).
(4) signal an error

By the way, I don't know why this function is necessary, in
what situation it is intended to use this function.

Currently, it is used only in cc-vars.el as below.

(defconst c-emacs-features
[...]
       ;; before and including Emacs 19.34
       ((and (fboundp 'char-table-p)
	     (char-table-p table))
	(setq entry (car (char-table-range table [?a]))))

but this is equivalent to 

	(setq entry (car (aref table ?a))))

---
Ken'ichi HANDA
handa@m17n.org