[CoFI] Revised concrete syntax for CASL basic specs

[pdmosses@brics.dk]

A revised proposal for the concrete syntax of basic specifications in
CASL has been installed:

  http://www.brics.dk/Projects/CoFI/Documents/CASL/SyntaxIssues/
  ftp://ftp.brics.dk/Projects/CoFI/Documents/CASL/SyntaxIssues/

A copy of the abstract is given below.

----   --------------------------------------------
\  /  | Peter D Mosses         <pdmosses@brics.dk> |
CoFI  | Common Framework Initiative  - Coordinator |
/  \  | WWW URL: http://www.brics.dk/Projects/CoFI |
----   --------------------------------------------

                          Concrete Syntax for CASL
                            Basic Specifications

                               Peter D. Mosses

                               6 October 1997

Abstract

     This proposal for the concrete syntax of basic specifications in
     CASL is intended as a compromise between the earlier proposals
     from Bremen [KB97] and Paris [VBC97].

     Main changes from the previous proposal (4 September):

        * The different `concise' and `verbose' versions of both input
          syntax and display format have been eliminated.
        * The longer keywords have been abbreviated, and both plural
          and singular forms are allowed.
        * The components of constructs in datatype declarations are now
          written using the same notation as for argument sort lists.
        * The grammar for the input syntax has been derived
          systematically from that of the abstract syntax.
        * The relation between the input and display of CASL symbols is
          now described separately.

     Appendix A lists the remaining points to be resolved by discussion
     on the CoFI Language Design mailing list, cofi-language@brics.dk.

     Deadline for comments: Monday 20 October 1997!

     See Appendix B for details of previously-discussed and resolved
     points.

     Examples of specifications illustrating the proposed concrete
     syntax have been posted on the cofi-language mailing list, and
     should soon become available as an appendix to this document.
     Readers are encouraged to test the proposal on their own
     specifications.

     An extension of this proposal to structured and architectural
     specifications is to follow as soon as possible.

     The author thanks Michel Bidoit, Christine Choppy, Bernd
     Krieg-Brückner, Till Mossakowski, and Frédéric Voisin for their
     energetic reactions to questionaires and tentative proposals, and
     for their willingness to make compromises. The discussions of
     concrete syntax during the CoFI meetings in Amsterdam (27
     September 1997) were particularly helpful. Thanks also to Mark van
     den Brand for producing a prototype parser for CASL (basic
     specifications) using ASF+SDF. The responsibility for any
     infelicities in the present proposal is, however, entirely the
     author's.

   * 1 Introduction
   * 2 Input Syntax
   * 3 Display Format
   * 4 Disambiguation
   * 5 Lexical Syntax
   * 6 Comments and Annotations
   * Appendices:
   * 7 Remaining Issues for Discussion
   * 8 Previous Issues for Discussion
   * References

(12 pages)