CoFI semantics task group

[Don Sannella <dts@dcs.ed.ac.uk>]

Dear friends,

The last message to this mailing list was a reminder in early January
to contribute to task B0 (annotating the CASL Language Design summary
with notes concerning questions and doubts).  Even though not many
people responded -- perhaps because nobody has any questions! -- it
took us a long time to prepare for the next step.  But we are there
now, finally.  Let's all try to avoid further delays so that we can
make some significant progress between now and the IFIP WG1.3 meeting
in June!

Topics below:

1. Result of task B0 available
2. Assignment of work for task B1
3. Meeting during TAPSOFT
4. Reminder about Task A

Best regards,
Don and Andrzej

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1. Result of task B0 available

The CASL Language Summary, with annotations concerning questions and
doubts, is now available on the CoFI pages:

DVI:	      ftp://ftp.brics.dk/Projects/CoFI/Notes/S-1/doc.dvi
Postscript:   ftp://ftp.brics.dk/Projects/CoFI/Notes/S-1/doc.ps.Z
Latex source: ftp://ftp.brics.dk/Projects/CoFI/Notes/S-1/doc.tex
Hypertext:    http://www.brics.dk/Projects/CoFI/Notes/S-1/

Please have a look, and send expressions of admiration and thanks to
the contributors.

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2. Assignment of work for task B1

Recall that task B1 was to extend each section of the annotated
Language Summary by English text explaining the semantics of all the
concepts and constructs in that section.  For the "Concepts" sections,
this should include an attempt at formally defining the semantic
domains it introduces, under the assumption that semantic domains
introduced elsewhere are already defined.

Each part of the Language Summary will have one or more authors and
one kibitzer(*).  The authors are responsible for actually doing the
work.  The kibitzer will act as first reader of what is produced, act
as devil's advocate, push the authors to do the work, and perhaps jump
in and help if needed.

(*) kibitzer, n.  Meddlesome person, one who gives advice
gratuitously; one who watches a game of cards from behind the players.

Authors and kibitzers are as follows (additional volunteers welcome!):

  Basic specifications: Don (kibitzer Hubert)
  Subsorting: Anna and Maura (kibitzer Till)
  Structured specifications: Till and Hubert (kibitzer Andrzej)
  Architectural specifications: Andrzej (kibitzer Don)
  Libraries: Peter (kibitzer Hans-Joerg)

The goal is to have this step finished by TAPSOFT (14-18 April).  Here
is a timetable:

  VERY SOON: Don sends the relevant part of the latex source to the
  first-named authors listed above.

  DURING MARCH: Authors work, kibitzers ask how they are getting on.

  FRIDAY 28TH MARCH: Authors send a first version to the kibitzer.

  MONDAY 7TH APRIL: Kibitzer sends a finished draft to Don.

  BEFORE TAPSOFT: Don delivers the result of task B1.

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3. Meeting during TAPSOFT

There will be a meeting of the CoFI semantics task group at TAPSOFT on
Wednesday 16th April after the last session.  (For information about
TAPSOFT, see http://www.lifl.fr/tapsoft97/, and note that the early
registration deadline is 14th March.)  Some topics for discussion
will be: the result of tasks A and task B1; semantic domains; style of
semantics; preparation for task B2.

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4. Reminder about Task A

Task A was to study potentially problematic areas of the language.
The following list of topics with suggested authors was sent out at
the end of November.  Please look to see what you are supposed to do
and do it as soon as possible.  Authors should publish notes on the
CoFI pages when they are finished by sending them to Peter Mosses.
Please aim to have all these done before TAPSOFT.  If you keep them
short and to the point then this should not be much work!!

   - Many-sorted and subsorted logic
     (ACTION: Subsorting group = Maura, Anne, Till)

   - Interaction of subsorting and structured specification
     (ACTION: Subsorting group)

   - Type definition groups and sort generating constraints
     (ACTION: Subsorting group, Bernd, Peter)

   - Interaction of compound identifiers with subsorting
     (ACTION: Subsorting group, Michel)

   - Generic specifications
     (ACTION: Andrzej, Hubert, Hans-Joerg, Fernando)

   - Static semantic conditions for signature morphisms, unions and
     compound identifiers
     (ACTION: Don, Andrzej, Fernando, Hubert, Subsorting group)

   - Static semantic conditions for EXTENSIONs, SPEC-DEFNs and
     UNIT-SPECs
     (ACTION: Andrzej, Hubert, Fernando) 

   - Interaction of compound identifiers with signature morphisms
     (ACTION: Andrzej, Michel)
     *** DONE *** see ftp://ftp.brics.dk/Projects/CoFI/Notes/S-2.txt

   - Architectural specifications
     (ACTION: Andrzej, Don, Fernando, Peter)

   - Glimpse at extension to higher-order?
     (ACTION: Anne?, Bernd)