The Logic of the RAISE SpeciFcation
and Anne E. Haxthausen
International Institute for Software Technology, United Nations University,
Department of Informatics and Mathematical Modelling, Technical University of
Denmark, Lyngby, Denmark,
This chapter describes the logic of the RAISE SpeciFcation Language,
RSL. It explains the particular logic chosen for RAISE, and motivates this choice
as suitable for a wide-spectrum language to be used for designs as well as initial
speciFcations, and supporting imperative and concurrent speciFcations as well as
applicative sequential ones. It also describes the logical deFnition of RSL, its ax-
iomatic semantics, as well as the proof system for carrying out proofs. ±inally, a
case study illustrates speciFcation and veriFcation methods in RAISE.
formal methods, logic, proof, RAISE, RSL
An important technique for increasing the reliability of software systems is
to use formal development methods. Formal methods provide mathematically
based languages for specifying software systems and proof systems for veri±-
cation purposes. During the last two decades a whole range of formal methods
have been developed. One of these is RAISE.
The goal of this chapter is to describe and motivate the logic of the RAISE
speci±cation language, RSL. This logic is non trivial and interesting because
the language supports many di²erent speci±cation styles.
It should be noted that for a given, formal language the term ‘logic’ can
be used in two di²erent but related senses. It may refer to the meanings of
the ‘logical’ (truth-valued) expressions of a language. Alternatively, ‘logic’ may
refer to the proof system, to the inference rules by which one may reason about
terms of the language. In designing a language, choices made in the assignment
of meanings to expressions inﬂuence the possible design of the proof system.
For this reason we have chosen to use the term ‘logic’ as encompassing both
In the remaining part of this section, we give a short introduction to RAISE
including a survey of the major speci±cation styles supported by RSL. Then,