TAPSOFT '95: Theory and Practice of Software Development: 6th International Joint Conference CAAP/FASE Aarhus, Denmark, May 22–26, 1995 Proceedings

826 Pages·1995·13.977 MB·English

by  Hartmut Ehrig, Bernd Mahr (auth.), Peter D. Mosses, Mogens Nielsen, Michael I. Schwartzbach (eds.)

Lecture Notes in Computer Science 915
Edited by G. Goos, J. Hartmanis and J.van Leeuwen
Advisory Board: W. Brauer D. Gries J. Stoer
Peter D. Mosses Mogens Nielsen
Michael I. Schwartzbach (Eds.)
TAPSOFT '95:
Theory dna Practice
of Software Development
6th International Joint Conference CAAP/FASE
Aarhus, Denmark, May 22-26, 5991
Proceedings
r e g n@ i r p S
Series Editors
Gerhard Goos
Universit~t Karlsruhe
Vincenz-Priessnitz-Strage 3, D-76I 28 Karlsmhe, Germany
Juris Hartmanis
Department of Computer Science, Cornell University
4130 Upson Hall, Ithaca, NY 14853, USA
Jan van Leeuwen
Department of Computer Science, Utrecht University
Padualaan ,41 3584 CH Utrecht, The Netherlands
Volume Editors
Peter D. Mosses
Mogens Nielsen
Michael I. Schwartzbach
BRICS, Department of Computer Science, University of Aarhus
Ny Munkegade, Bldg. 540, DK-8000 Aarhus C, Denmark
CR Subject Classification (1991):D.2. !-2, D.2.4-7, D.2.10, D.3.1-4, E 1.1-2, E2.2,
E3.1-3, F.4.1-3, K.6.3, B.2.3
ISBN 3-540-59293-8 Springer-Verlag Berlin Heidelberg New York
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Preface
TAPSOFT 59' is the Sixth Intrnational Joint Con ference on the Theory and
Practice of Software Developmem, s-~c*~iT at the University of Aarhus,
Denmark, 22-26 May, .5991
The TAPSOFT series was started in Berlin in 1985, on the initiative of
Hartmut Ehrig, Bernd Mahr, and Christiane Floyd (among others). Since then
TAPSOFT has been held biennially, in Pisa (1987), Barcelona (1989), Brighton
(199t), and Orsay (1993). The overall aim of TAPSOFT saw formulated :sa
to bring together theoretical computer scientists and software engineers
(researchers and practitioners) with a view to discussing how fo~nal
methods can usefully eb applied in software development.
As part of TAPSOFT '95, Ehrig, Mahr, and Floyd review what has been achieved
within the TAPSOFT area dtlring the past decade, and consider prospects for
the future. Moreover, there is to be a session to debate the generM organization of
European Spring Conferences on Software Science (including TAPSOFT). This
10th anniversary of the start of TAPSOFT looks as if it will be a significant
turning point in the development of the series.
TAPSOFT traditionally comprises three parts:
Invited Lectures:
-
by leading researchers, on a variety of relevant topics;
CAAP: Colloquium on Trees in Algebra and Programming
-
covering a wide range of topics in theoretical computer science;
FASE: Colloquium on Formal Approaches in Software Engineering
-
with the emphasis on practical applicability.
In recognition of the importance of support tools for practical use of formal
approaches in software development, TAPSOFT 59' includes a fourth part:
TOOLS:
-
two plenary sessions for tool demonstrations, as well as facilities for
individual demonstrations.
Satellite Meetings
The following three satellite meetings are to take place in conjunction with TAP-
SOFT '95: TACAS (Workshop on Tools and Algorithms for the Construction
and Analysis of Systems, 19-20 May); TPA (Workshop on Types for Program
Analysis, 26-27 May); and COMPASS WG Day (for Members of ESPRIT BR
Working Group 6112, 26-27 May).
Committee:
TAPSOFT Steering
Andr~ Arnold, Pierpaolo Degano, Hartmut Ehrig, Marie~Claude Gaudel,
Tom Maibaum, Ugo Montanari, Maurice Nivat, Fernando Orejas.
vI
Invited Lectures
In their paper A Decade of TAPSOFT: Aspects of Progress and Prospects in
Theory and Practice of Software Development, Hartmut Ehrig and Bernd Mahr
discuss the general background of TAPSOFT, and focus on specific aspects of
theory and practice which seem to them to be typical of TAPSOFT: the support
of software development by algebraic methods, techniques and tools. They also
give their expectations for the future of TAPSOFT and its topics.
In Theory and Practice of Software Development - Stages in a Debate, Chris-
tiane Floyd discusses the place of formal methods in software development. She
distinguishes two notions of theory: the mathematical science of computation
and the treatment of computing as a human activity. Fundamental assumptions
underlying formal methods and their relation to emancipatory approaches such
as participatory design are discussed. The paper closes with a call for a dialogica~
framework for further pursuing these questions.
In Testing Can Be Formal, Too, Marie-Claude Gaudel presents a theory of
program testing based on formal specifications. The formal semantics of the
specification is the basis for a notion of an exhaustive test set. She also considers
the problem of observability of the results of a program with respect to its
specification, and proposes a solution in the case of algebraic specifications.
In the paper Formal Methods and Social Context in Software Development,
Joseph Goguen and Luqi explore some reasons why formal methods have not
been accepted to the expected extent. One major problem has been that formal
methods have not taken sufficient account of the social context of computer
systems. To better understand social context, they discuss ethnomethodology, a
branch of sociology, and situated abstract data types, whic~ help bridge the gap
between the technical and the social. The paper concludes with discussions of
software composition and a new paradigm of "Domain Specific Formal Methods".
Set constraints have been used extensively in program analysis and type
inference. In Rational Spaces and Set Constraints, Dexter Kozen investigates
the topological structure of the spaces of solutions to systems of set constraints.
He develops the theory of rational spaces and derives generalizations and proofs
from topological principles of some results in the literature on set constraints.
Vaughan Pratt has been closely involved with analysing the significance of the
recently revealed bug in the Intel Pentimn computer chip. His topical paper on
the Anatomy of the Pentium Bug presents general background and new results.
The software engineering implications of the bug include the observations that
the method of exercising reachable components cannot detect reachable compo-
nents mistakenly believed unreachable, and that hand-checked proofs build false
confidence.
In his other invited paper, Rational Mechanics and Natural Mathematics,
Pratt works with so-called Chu spaces, which have fbund applications in com-
puter science, mathematics, and physics. He uses Chu spaces and residuation to
derive all causal interaction, both between and within two planes, from a uniform
and algebraically rich theory of between-plane interaction alone, and addresses
fundamental philosophical questions.
vii
CAAP '95:
Colloquium on Trees in Algebra and Programming
Programme Committee:
Andrfi Arnold (Prance) Jan Willem Klop (Netherlands)
Bruno Courcelle (France) Ugo Montanari (Italy)
Josep Dfaz (Spain) Mogens Nielsen (chair, Denmark)
Volker Diekert (Germany) Colin Stirling (Britain)
Hartmut Ehrig (Germany) Wolfgang Thomas (Germany)
Juhani Karhum/iki (Finland) Sophie Tison (Prance)
This colloquium series was originally devoted to the algebraic and combina-
torial properties of trees, and their r61e in various fields of computer science.
The importance of trees in computer science is now firmly established, and the
study of their algebraic, logical, and combinatorial properties has made signif-
icant progress. Many other structures such as graphs are playing similar roles
and deserve similar theoretical studies. In keeping with CAAP's traditions while
accounting for these new trends, CAAP '95 covers algebraic, logical and com-
binatorial properties of discrete structures and their applications to computer
science.
Out of 17 submitted papers, the programme committee selected 23 for presen-
tation at the conference. These are grouped into sessions on trees and automata,
concurrency, logic and specification, formal languages, rewriting systems, and
semantics.
FASE '95:
Colloquium on Formal Approaches in Software Engineering
Programme Committee:
Egidio Astesiano (Italy) Bernd Mahr (Germany)
David Basin (Germany) Fernando Orejas (Spain)
V~ronique Donzeau-Gouge (France) Don Sannella (Britain)
Marie-Claude Gaudel (France) Michael Schwartzbach (chair, Denmark)
Bengt Jonsson (Sweden) Bernhard Steffen (Germany)
Paul Klint (Netherlands) Reinhard Wilhelm (Germany)
This colloquium aims at being a forum where different formal approaches to
problems of software specification, development, and verification are presented,
compared, and discussed.
Out of 76 submitted papers, the programme committee selected 21 for pre-
sentation at the conference. These are grouped into sessions on types, tools,
static analysis, case studies, transformations, concurrency, and specifications.
TOOLS
The two plenary TOOLS sessions at TAPSOFT '95 are to provide demonstra-
tions of nine relevant systems altogether. Moreover, there are to be facilities for
iiiv
further demonstrations of these and other systems in the breaks and during the
parallel sessions. It is hoped that this will give the TAPSOFT participants a
useful opportunity to assess some of the main tools that are currently available,
and that tool demonstrations will be a regular feature of future TAPSOFT con-
ferences. The demonstrations are documented by 2-page summaries, printed at
the back of this proceedings.
Acknowledgments
The organizers gratefully acknowledge the following support:
The TAPSOFT Steering Committee made the decision to hold TAPSOFT '95
in Aarhus in good time, and gave a lot of useful advice about organization.
The CAAP and FASE Programme Committee members had the difficult task
of selecting papers from a satisfyingly large number of submissions; fortunately
most of them (20 out of 24) were able to attend the selection meeting. Almost
300 referees, listed on the following pages, provided reports on the submitted
papers. Michael Schwartzbach developed the system by which referee reports
could be submitted directly to a database using WWW forms, with programme
committee members being automatically informed of any major differences of
assessment on particular papers.
The invited lecturers have written a varied and exciting collection of hill
papers to support their lectures. Special thanks to Vaughan Pratt for the paper
on the Pentium bug, which was a last-minute addition to the TAPSOFT '95
programme.
Karen K. Mr has efficiently managed the preparation of the proceedings,
as welt as many other aspects of the organizationl her assistance has been (and
still is!) indispensable.
Alfred Hofmann at Springer-Verlag kindly agreed to publish the proceedings
in the Lecture Notes in Computer Science series, and helped with its preparation.
BRICS (Centre for Basic Research in Computer Science: a centre established
in cooperation between the Danish NationM Research Foundation, the University
of Aarhus and Aalborg University) is the host for TAPSOFT '95.
The following organizations are sponsoring TAPSOFT '95:
- ,COMPASS: ESPRIT Basic Research Working Group 6112: a COMP-
rehensive Algebraic approach to System Specification and development
- DAII~I: Department of Computer Science, University of Aarhns, Denmark
- EATCS: European Association for Theoretical Computer Science
- SNF: Danish Science Research Council
- University of Aarhus: Faculty of Science, University of Aarhus, Denmark
TAPSOFT 59~ Organizing Committee: Karen K. Moller,
Peter D. Mosses (chair), Mogens Nielsen, Michael L Schwartzbach.
Aarhus, February 1995 Peter D. Mosses
Referees L. Qristoff R. Glas
A. C~e,~ .S Gnesi
P. Abdulla M. Clerbout W. Goerigk
J.R. Abrial .S Clgrici .M Goldwurm
M. Alt E. Contejean W. Grieskamp
R. Amadio F. Cornelius A. Griffault
T. Amtoft A. Corradini J,F. Groote
.M Ancona G. Costa M. Grosse-Rhode
H.R. Andersen M. Dam G. Guaiana
P. Anderson O. Danvy .S Giindel
.S Anderson M. Dauchet A. Habel
R. Andonov R. De Nicola N. Halbwachs
M,-V. Aponte P. Degano C. Hankin
K. Apt .M Deininger H. Hansen
P. Audebaud J. Delacroix M. Hanus
S.J. van Bakel F. Denis T. Hardin
H. Baumeister J. Deset K. Havelund
J. Beauquier A. Deutsch A. Heckler
M. Bellia P. Devienne J. tIeering
K. Bennacer R. DiCosmo A, Hense
B. B~rard A. Dicky C. Hermida
R. Berghammer K. Didrich D. Hofbauer
J.A. Bergstra .S Diehl J. Honkala
E. Best G. Dowek F. Honsell
J. B6tr6ma C. Dubois O.I. Hougaard
M. Bidoit W. Ebinger J. Hromkovic
P. Binderup U. Engberg M. Huhn
J. Blanco U.H. Engberg H. Htmgar
J. Blom J. Engelfriet H. Hfittel
A. Bockmayr J. Esparza J.M. hie
F.S. de Boer P. Facon P. Inverardi
M. Boreale R. Fagerberg D. Janin
D. Bosscher P. Feautrier M. Jantzen
A. Bouali C. Fecht C. Jard
P. Boullier C. Ferdinand K. Jensen
J. Boyar G. Ferrari T. Jensen
J. Bradfield A. Finkel M. Jerrum
M.G.J. van den Brand G. Florin B. Josko
F. Brandenburg M. Fokkinga .M Jourdan
G.S. Brodal G. Frandsen .S Kahrs
M. Broy D. de Frutos Escrig R. Kaivola
G. Bruns .M Fuchs K. Kalorkoti
A. Bundy J. Gabarro J.F.T. Kamperman
O. Burkart F. Gadducci L. Kempe
I. Castellani H. Ganzinger R. Kennaway
P. Casteran R. Gavalda M. Kindahl
M. Cerioli G. Germano P. King
A. Cheng A. Geser C. Kirchner
C. Choppy G, Ghelh H. Kirchner
I. Christoff .S Gilmore N. Klarlund
.S Klusener A. Nonnengart L. Seinturier
J. Knoop O. Nurmi M.J. Serna
M. Korff S.-O. NystrSm .M Siegel
H. Kroeger E. Ohlebusch J. Sifakis
R. Kuiper J. van Oosten F. Simon
A. van Lamsweerde V. van Oostrom H. Sips
C. Laneve Y. Ortega Malt~n A. Skou
B. Lang F, Otto A. SmaiU
K.G. Larsen J. Padberg L. Staiger
M. Latteux C. Palamidessi P. Stockier
B. Le Sa~c J. Palsberg P. Stevens
H. Leseow .H Partsch K. Stoelen
J.J. Ldvy R. Pefia .M Sudholt
G. Luettgen D. Poled K. Sunesen
D. Lutzebgck R.P. Perez A. TSnne
C. Lynch H. Petersen P.S. Thiagarajan
G. M61an~on C. Petersohn K. Tolksdorf
A. Maggiolo A. Petit J. Trescher
K. Malmkjmr P. Pettersson D. Troeger
J. Marcinkowski B. Pierce Y.-K. Tsay
T. Margaria G. Pighizzini D. ~ri
J.Y. Marion G. Plateau J. Underwood
B. Marre D. Plump F.W. Vaandrager
N. Marti-Oliet A. Podelski E. Valkema
M. Martelli A. Poetzsch-Heffter B. Victor
P.-E. Martin A. Potthoff G. Vidal-Naquet
C. Martinez D. Pyre L. Vigano
.S Martini P. Quaglia E. Visser
A. Masini C. Queinnee ~W Vogler
A. Mateeseu G. Reggio F. Voisin
D. Matthews K, Reinhardt G. Wall
.S Matthews L. Rigeiro H.R. Walters
B. Mayoh U. Roester ~A Weber
L. Meertens J o Roman sK ~Veihrauch
E. Meijer F. Rouaix C. Weise
P.-A. Mellies G. Rfinger W. Weisweber
E. Mikk O. Ruthing R. Whitty
H. Miliroth ~J Rutten .S Wiebrock
K. Mitchell M. Ryan T. Wilke
E. Moggi G, Saake .M Wirsing
B. MSller N. Saheb M. W01f
R. Mmtroy P. Sall~ U. Wolter
F. Morando A. Salomaa D. Wolz
P.D. Mosses K, Salomaa K. Yi
F. Mourlin D. Sangiorgi W. Yi
A. Muscholl V. Sassone P. Zeitz
M. Navarro H.J. Schneider .S Zhou
F. Nielson T. Schgbel-Theuer W. Zielonka
H,R. Nielson H. Seidl E. Zucca
Table of Contents
I Invited Lectures 1
A Decade of TAPSOFT: Aspects of Progress and Prospects
in Theory and Practice of Software Development .............. 3
H. Ehrig, B. Mahr
Theory and Practice of Software Development - Stages in a Debate . . . 25
C. Floyd
Rational Spaces and Set Constraints ..................... 42
D. Kozen
Formal Methods and Social Context in Software Development ....... 62
J.A. Goguen, Luqi
Testing Can Be Formal, Too ......................... 82
M.-C. Gaudel
Anatomy of the Pentium Bug ......................... 97
V. Pratt
Rational Mechanics and Natural Mathematics ................ 108
V. Pratt
II CAAP 123
CAAP-I: Trees :& Automata
First-Order Logic on Finite Trees ....................... 125
A. Potthoff
Decidability of Equivalence for Deterministic Synchronized Tree
Automata .................................... 140
K. SaIomaa
The Equivalence Problem for Letter-to-Letter Bottom-up Tree
Transducers is Solvable ............................ 155
Y. Andrd, F. Bossut
CAAP-2: Concurrency I
uI: A Symmetric Calculus based on Internal Mobility ........... 172
D. Sangiorgi
Complete Inference Systems for Weak Bisimulation Equivalences in
the r-Calculus ................................. 187
H. Lin