Transformation of Applicative Specifications into Imperative ...

13.4. CONCLUDING REMARKS
Translation from applicative code into imperative code has been considered
before. The reason is that assembly code is imperative. This means
that when compiling applicative programming languages such as Scheme,
SML and some parts of Lisp transformation from applicative program into
imperative assembly code is necessary. Many of the techniques used when
compiling applicative programs cannot be exploited when developing transformation
rules for this project as assembly code and RSL specifications are
very different. But a few techniques can. This includes techniques for removing
recursions, techniques that can be applied if extending the transformer
to cover a greater part of the transformation from applicative RSL specification
into imperative RSL specification. One of these techniques is the use
continuations as described in [Wan80]. The drawback of using continuations
compared to e.g. loops is a lack of clearness in most cases.
The work described in [Lin04] and [LH04] considers the possibility of
translating specifications written within a the mRSL subset of RSL and
proof obligations into higher-order logic (HOL) specifications and proof obligations
in order to be able to use the generic proof assistant Isabelle. In
this way the the proof support for the RAISE Development Method could
be improved. The project is primarily theoretical and defines among other
things an institution for mRSL as mentioned in Chapter 7.
The results of the related work are used to the extend possible, but as
much of the work of this project never has been done before, it has been
done without the possibility of support from related work.
13.4 Concluding Remarks
This project has been an instructive experience for me. First of all I have
had the opportunity to try my strength against theoretical work, which have
been both challenging and fun. Furthermore, the project has given me a
better understanding of language processors and translation. Last but not
least, by working a lot with RSL and the RAISE method I have gained a
lot of experience in these – an experience I hope to be able to utilize when
entering the labour markets.
It is my belief that the use of formal methods will increase in the years
to come due to two facts. First of all the amount of safety critical systems
will increase and at the same time the formal methods will be improved as
more and more tools will be developed. My hope is, that this project and
the resulting transformer will have a positive influence on this development.
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