Subject: N 3751-Letter from JTC 1/SC 22 to JTC 1/SC 2 Requesting that JTC 1/SC 2 Consider Putting Specification of the Character Repertoire for Ide ntifier on the SC 2 Programme of Work

From: Sally Seitz <[email-masked]>
Date: Fri, 18 Jun 2004 16:02:49 -0400

ISO/IEC JTC 1/SC22

Programming languages, their environments and system software interfaces

Secretariat:  U.S.A.  (ANSI)

ISO/IEC JTC 1/SC22 N3751

TITLE:

Letter from JTC 1/SC 22 to JTC 1/SC 2 Requesting that JTC 1/SC 2 Consider
Putting Specification of the Character Repertoire for Identifier on the SC 2
Programme of Work    

DATE ASSIGNED:

2004-06-18

SOURCE:

SC 22 Secretariat

BACKWARD POINTER:

DOCUMENT TYPE:

Other (Defined)

PROJECT NUMBER:

STATUS:

This letter has been sent to the Chair and Secretary of JTC 1/SC 2 from the
Chair and Secretary of JTC 1/SC 22 on behalf of JTC 1/SC 22.  The Japanese
National Body incorporated comments received from N 3725.

ACTION IDENTIFIER:

FYI

DUE DATE:

DISTRIBUTION:

TEXT 

CROSS REFERENCE:

N3673, N3725

DISTRIBUTION FORM:

Def

Address reply to:

ISO/IEC JTC 1/SC22 Secretariat

Sally Seitz

ANSI

25 West 43rd Street

New York, NY  10036

Telephone:  (212) 642-4918

Fax:             (212) 840-2298

Email:  [email-masked]

_______________________end of cover page, beginning of
document_______________

18 June 2004

Dear Dr. Shibano and Ms. Kimura,

SC 22 would like to make a request to SC 2/WG 2, such that whenever SC 2/WG
2 adds new characters to ISO 10646, SC 2/WG 2 also specifies those new
characters that would be acceptable as identifiers. 

The background of the request:

1) Currently TR 10176 (The guidelines for preparation of programming
language standards), a project of SC 22, provides a guideline for character
repertoire to be allowed for identifiers in Annex A (Recommended extended
repertoire for user-defined identifier). SC 22 has been revising Annex A of
TR 10176 following the revisions of ISO/IEC 10646 in order to be
synchronized with character property of the Unicode standard. However, SC
22's revision work could not be started before the publication of the
revised edition of ISO/IEC 10646, therefore the content of Annex A of TR
10176 is not in agreement with the latest edition of ISO/IEC 10646. If SC 2
specifies character repertoire for identifiers, the technical contents of TR
10176 would become synchronized with the future editions of ISO/IEC 10646.

2) The work of identifying extended characters is likely to have broad
interest to JTC 1 subcommittees, such as SC 7, SC 22, SC 23, SC 25, SC 28,
SC 31, SC 32, SC 34, SC 35, and SC 36. It is recommended that this work be
circulated at the JTC 1 level so that JTC 1 subcommittees may be better
informed of these SC 2 activities, and so that JTC 1 subcommittees may
harmonize their work with the SC 2 activities.

SC 22's consideration to be kept in mind:

In addition to identifying extended identifier characters, it may be
important for many ICT applications to know what characters are also
considered extended digit characters, extended letter characters, and other
classes of extended special characters.

In prior work on extended identifiers, knowledgeable experts provided advice
and guidance that helped properly classify characters. It would be extremely
helpful to capture this knowledge in a "rationale/criteria annex" or a
companion technical report so that users of these classifications could be
better informed about the intended uses, the special circumstances, the
limitations, and so on.

While it is not necessarily a classification function, certain relationships
are important for common operations on identifiers, such as the familiar
upper-lower case usage in Latin letters (e.g., leading capitals, "camel
case", etc.). It has been discovered that additional character
transformations for identifiers are in use in non-Latin scripts in ICT
applications (e.g., full vs. half width for Japanese identifiers). It would
be helpful if the character set experts in SC 2 could identify some of these
popular conventions so that they could be better understood and processed
more consistently in ICT environments.

SC 22 would like to ask SC 2/WG 2 to specify those characters which they
believe are suitable for identifiers, leaving each programming language
standard (SC 22 and other SCs and work programs generally) free to specify
its own identifier-character list after considering the tradeoffs between
its requirements and the advantages of a consistent, single, identifier
specification in the same manner as the current TR 10176 recommends that
programming language standards can extend or restrict the identifier
character list.

SC 22 would like to request that SC 2 respond to this question by August
2004 if possible.

On behalf of JTC 1/SC 22,

John Hill, Chairman

Sally Seitz, Secretary

Sally Seitz

Program Administrator

ANSI

25 West 43rd Street

New York, NY 10036

Phone: (212) 642-4918

Fax: (212) 840-2298