Public Comment Number PC-UK0081

ISO/IEC CD 9899 (SC22N2620) Public Comment

=========================================== 

Date: 1998-02-25
Author: N.M Maclaren
Author Affiliation: Self
Postal Address:
    University of Cambridge,
    Computer Laboratory,
    New Museums Site,
    Pembroke Street,
    Cambridge CB3 3QG,
    United Kingdom
E-mail Address: <nmm1@cam.ac.uk>
Telephone Number: +44 1223 334761
Fax Number:       +44 1223 334679
Number of individual comments: 1


Comment 1. 

Category: Normative change to existing feature retaining the original intent

Committee Draft subsection: 5.1.1.2, 6.1.3.4, 6.1.4, Annex B

Title: Universal character names and character constants


Detailed description:

If both the basic source and basic execution character sets include "$"
(which is implementation-defined in both C89 and C9X), the following is
true in C89:

    #include <limits.h>
    #if '$' <= UCHAR_MAX

But this is NOT required by the current wording of paragraphs 10 and 11 in
C9X, which leaves this case implementation-defined even if both the basic
source and basic execution character sets include '$'.  This is because the
'$' expands to '\u0024', and the wording in those sections makes it quite
clear that '\u0024' is neither a single character nor an escape sequence.
Note that this affects ONLY translation phase 4, because phase 5 deals with
the problem.

I suggest moving "universal-character-name" in the Syntax section of 
6.1.3.4 Character constants from being an entry in "c-char" to being one in
"escape-sequence".  This also needs to be done in 6.1.4 String literals and
both places in Annex B, of course, but I can't see that it introduces any
problems in any of them or other sections.