From: zforum-request@comlab.ox.ac.uk
Newsgroups: comp.specification.z,news.answers
Subject: comp.specification.z Frequently Asked Questions (Monthly)
Summary: Information about the Z formal specification notation
Date: 1 Jan 93 02:00:10 GMT
Expires: Fri, 12 Feb 1993 02:00:04 GMT
Reply-To: zforum-request@comlab.ox.ac.uk
Followup-To: comp.specification.z
Organization: Oxford University Computing Laboratory, UK
Supersedes: <z-faq_723175204@newsserv>
Originator: news@topaz.comlab

Archive-name: z-faq
Last-modified: 1 Dec 1992


NAME:     comp.specification.z
STATUS:   unmoderated
PURPOSE:  Discussion concerning the formal specification notation Z.

(If you have read this before, changed and new sections are marked with
`|' in the right hand margin.)

Questions have been marked with "Subject:" at the start of the line to
allow some newsreaders to scan them easily (e.g., "^G" within "rn").

Subject: What is it?

The comp.specification.z USENET newsgroup was established in June 1991
and is intended to handle messages concerned with the formal
specification notation Z. It has an estimated readership of around
20,000 people worldwide.  Z, based on set theory and first order
predicate logic, has been developed at the Programming Research Group
(PRG) at the Oxford University Computing Laboratory and elsewhere for
well over a decade.  It is now used by industry as part of the software
(and hardware) development process in both the UK and the US. It is
currently undergoing BSI standardization in the UK.  Comp.specification.z
provides a convenient forum for messages concerned with recent
developments and the use of Z.  Pointers to and reviews of recent books
and articles are particularly encouraged. These will be included in the
Z bibliography (see below) if they appear in comp.specification.z.

Subject: What if I know someone interested without access to USENET news?

Electronic mailing list: There is an associated Z FORUM mailing list
that was initiated in January 1986 by Ruaridh Macdonald, RSRE, UK.
Articles are now automatically cross-posted between comp.specification.z
and the mailing list for those whose do not have access to USENET
news.  This may apply especially to industrial Z users who are
particularly encouraged to subscribe and post their experiences to the
list.  Please contact <zforum-request@comlab.ox.ac.uk> with your name,
address and e-mail address to join the mailing list (or if you change
your e-mail address or wish to be removed from the list). Readers are
strongly urged to read the comp.specification.z newsgroup rather than
the Z FORUM mailing list if possible. Messages for submission to the Z
FORUM mailing list and the comp.specification.z newsgroup may be
e-mailed to <zforum@comlab.ox.ac.uk>.

Subject: What if I know someone interested without access to e-mail?

Postal mailing list: If you wish to join the postal Z mailing list,
please send your address to the industrial liaison secretary at OUCL,
11 Keble Road, Oxford OX1 3QD, UK (tel +44-865-272579, fax
+44-865-273839) or on <Joan.Arnold@comlab.ox.ac.uk>. This will ensure
you receive details of Z meetings, etc., particularly for people
without access to electronic mail.

Subject: What if I know someone interested without access to postal mail?

Be reasonable! :-)

Subject: How can I join in?

Subscribers: If you are currently using Z, you are welcome to introduce
yourself to the newsgroup and Z FORUM list by describing your work with
Z. You may also advertise any publications concerning Z which you or
your colleagues produce. These will then be automatically added to the
master Z bibliography maintained at the PRG and updated for the annual
Z User Meetings held each December.

Subject: Where are the back issues and other public Z-related files?

Archive: There is an automatic mail-based electronic archive server at
the PRG which contains all the back-issues and messages on Z FORUM and
comp.specification.z, as well as a selection of other Z-related files.
Send an e-mail message containing the command "help" to the address
<archive-server@comlab.ox.ac.uk> for further information on how to use
the server. A command of "index z" will list the Z-related files.
If you have serious trouble accessing the archive server, please
contact the address <archive-management@comlab.ox.ac.uk>.

FTP access: The archive is also available via anonymous FTP on the
Internet. Type the command "ftp ftp.comlab.ox.ac.uk" (or alternatively
"ftp 192.76.25.2" if this does not work) and use "anonymous" as the
login id and your e-mail address as the password when prompted. The FTP
command "cd Zforum" will get you into the Z archive directory.  The
file "README" gives some general information and "00index" gives a list
of the files. (Retrieve these using the FTP command "get README", for
example.)

Subject: What tools are available?

Tools: various tools for formatting, type-checking and aiding proofs
used Z are available.  A free LaTeX style file and documentation can be
obtained from the PRG archive server. To receive this via e-mail, send
a message containing the command "send z zed.sty zguide.tex" to the PRG
archive server (see above).  A similar style and type-checker called
fuzz are available commercially.  Send the command "send z fuzz" to the
archive server for an order form.
  CADiZ, a suite of tools for checking and typesetting Z specifications
is available from York Software Engineering, University of York, YORK
YO1 5DD, UK (tel +44-904-433741, fax +44-904-433744). This is based
around Unix troff, but LaTeX support is planned. Contact David Jordan
at York on <yse@minster.york.ac.uk> for further information.
  The B-Tool can be used to check proofs concerning parts of Z
specifications.  This is licensed by Edinburgh Portable Compilers Ltd,
17 Alva Street, Edinburgh EH2 4PH, UK (tel +44-31-225-6262, fax
+44-31-225-6644). Contact the Distribution Manager on the address
<support@epc.ed.ac.uk> for further information.  A Z proof tool called
zedB, which is based on the B-Tool, was presented at the 1991 Z User
Meeting; this may be made available in due course.

Subject: How can I learn about Z?

Courses: There are a number of courses on Z run by industry and
academia. Oxford University offers industrial short courses in the use
Z.  As well as introductory courses, recent newly developed material
includes advanced Z-based courses on proof and refinement, partly based
around the zedB tool.  Courses are held in Oxford, or elsewhere (e.g.,
on a company's premises) if there is enough demand. For further
information, contact Jim Woodcock (tel +44-865-272576, fax
+44-865-273839) on <Jim.Woodcock@comlab.ox.ac.uk>.
  Logica Cambridge offer a five day course on Z and a three day
introductory course on formal methods (mainly Z).  For dates and prices
contact Debi Kearney on +44-223-66343 ext 4859.
  Praxis Systems runs a range of Z (and other formal methods) courses.
For details contact Anthony Hall on +44-225-444700 or <jah@praxis.co.uk>.

Subject: What has been published about Z?

Publications: A BibTeX bibliography of Z-related publications is
available from the PRG archive server (see above).  Information on
Oxford University Programming Research Group (PRG) Technical Monographs
and Reports, including many on Z, is available from the librarian on
<library@comlab.ox.ac.uk>.
  The following books specifically concerning Z have been or are due to
be published (in approximate chronological order):

  I.Hayes (ed.), Specification case studies, Prentice Hall International
      Series in Computer Science, 1987.
  J.M.Spivey, Understanding Z: a specification language and its formal
      semantics, Cambridge University Press, 1988.
  D.Ince, An introduction to discrete mathematics and formal system
      specification, Oxford University Press, 1988.
  J.C.P.Woodcock & M.Loomes, Software engineering mathematics, Pitman, 1988.
  A.Diller, Z: an introduction to formal methods, Wiley, 1990.
  J.E.Nicholls (ed.), Z user workshop, Oxford 1989, Springer-Verlag,
      Workshops in Computing, 1990.
  B.Potter, J.Sinclair & D.Till, An introduction to formal specification
      and Z, Prentice Hall International Series in Computer Science, 1991.
  D.Lightfoot, Formal specification using Z, MacMillan, 1991.
  A.Norcliffe & G.Slater, Mathematics for software construction,
      Ellis Horwood, 1991.
  J.E.Nicholls (ed.), Z user workshop, Oxford 1990, Springer-Verlag,
      Workshops in Computing, 1991.
  I.Craig, The formal specification of advanced AI architectures,
      Ellis Horwood, September 1991.
  M.Imperato, An introduction to Z, Chartwell-Bratt, 1991.
  J.M.Spivey, The Z notation: a reference manual, 2nd ed., Prentice Hall
      International Series in Computer Science, 1992. (1st ed., 1989) +
  J.B.Wordsworth, Software development with Z, Addison-Wesley, 1992.
  S.Stepney, R.Barden & D.Cooper (eds.), Object orientation in Z,
      Springer-Verlag, Workshops in Computing, August 1992.
  J.E.Nicholls (ed.), Z user workshop, York 1991, Springer-Verlag,
      Workshops in Computing, 1992.
Announced:
  I.Hayes (ed.), Specification case studies, 2nd ed., Prentice Hall
      International Series in Computer Science, 1992.
  J.A.McDermid & P.Whysall, Formal system specification and implementation
      using Z, Prentice Hall International Series in Computer Science, 1992.
  J.C.P.Woodcock, Using standard Z, Prentice Hall International Series
      in Computer Science, 1992-93.

  + Widely considered as the current de facto standard for Z.

Subject: What is object-oriented Z?

Several object-oriented extensions to or versions of Z have been
proposed.  The book "Object orientation in Z", listed above, is a
collection of papers describing various OOZ approaches -- Hall, ZERO,
MooZ, Object-Z, OOZE, Schuman&Pitt, Z++, ZEST and Fresco (an OO VDM
method) -- in the main written by the methods' inventors, and all
specifying the same two examples.

Subject: How can I run Z?!

Z is a (non-executable in general) specification language, so there is
no such thing as a Z compiler/linker/etc. as you would expect for a
programming language. Some people have looked at animating subsets of Z
for rapid prototyping purposes, using logic and functional programming
for example, but this work is preliminary and is not really the major
point of Z, which is to increase human understandability of the
specified system and allow the possibility of formal reasoning and
development.

Subject: Where can I meet other `Z' people?
 
Meetings: VDM'91 was held on 21-25 October 1991, at Noordwijkerhout,
The Netherlands.  The meeting included papers on Z, and the proceedings
are available as two volumes in Springer-Verlag LNCS 551 (conference)
and 552 (tutorials). The scope of the symposium has expanded during
the last years to include other formal notations and techniques,
including Z. Therefore the name of the symposium will be changed to
Formal Methods Europe.  The first FME Symposium will be held at Odense
Technical College in Denmark, during the week of 19 to 23 April, 1993.
The programme chairman is Jim Woodcock, Oxford University Computing
Laboratory, 11 Keble Road, Oxford OX1 3QD, UK (tel +44-865-272576, fax
+44-865-273839, email <Jim.Woodcock@comlab.ox.ac.uk>). For further
details, send a message containing the command "send z fme93" to the
PRG archive server (see above).
  The 6th annual Z User Meeting was held on 16-17 December 1991, at the
University of York, England.  A 7th meeting with an industrial theme is
to be held on 14-15 December 1992 at the DTI (UK Department of Trade
and Industry), Victoria, London.  For further details, including a
registration form and information on the programme, send a message
containing the command "send z zmeeting92" to the PRG archive server
(see above).
  The 5th Refinement Workshop was held on 8-10 January 1992, at Lloyd's
Register of Shipping, Fenchurch Street, London, England. The proceedings
should also be published in the Springer-Verlag Workshops in Computing
series. The next workshop is planned for January 1994. Please contact
Roger Shaw on <ttercs@aie.lreg.co.uk> (tel +44-81-681-4747, fax
+44-81-681-6814) for further information.
  Details of Z-related meetings may be advertised on comp.specification.z
if desired. All the above meetings are likely to be repeated in some form.

Subject: What if I've spotted a mistake or omission?

Updates: Please send corrections or new relevant information about
meetings, books, tools, etc., to <zforum-request@comlab.ox.ac.uk>.
New questions and model answers are also gratefully received!

--
Jonathan Bowen, <Jonathan.Bowen@comlab.ox.ac.uk>
Programming Research Group, Oxford University Computing Laboratory, UK.