Re: [DotGNU]DotGNU and ASML

[Brian T Rice]

Hello Rhys,

On Tue, 2 Jul 2002, Rhys Weatherley wrote:
RW>Brian T Rice wrote:
RW>> So, I am offering a port of ASML to the dot-gnu platform. I can accomplish
RW>> an initial version using a program in the Maude language in just a month
RW>> or so, but Maude has not yet been shifted to the GPL; this license shift
RW>> is due in the fall.
RW>
RW>Sounds interesting.  As long as all software involved
RW>in implementing and using ASML is GPL-compatible then
RW>we shouldn't have a problem with it.
RW>
RW>Does Maude run natively on the host platform, or can
RW>it run on top of a CLR?

Maude's homepage, for reference, is http://maude.csl.sri.com/
Another description of the Maude family members is at
http://www.cs.ucsd.edu/users/goguen/sys/obj.html

It runs natively and is written in C++. It's a pre-existing specification
language that happens to be flexible enough that I can specify ASML's
syntax and semantics as a specification program within it. Maude runs on
most platforms that DotGNU supports, with the exception of Darwin (but not
Linux/PPC, ironically). Everything about Maude should be fixable once
released under the GPL in a few months. If that doesn't happen, I can
perform a clean-room re-implementation of ASML fairly easily, although it
will take more time.

There *does* exist the possibility of using another inference engine, but
it would probably result in a more convoluted program to implement the
language. There are several GPL prolog implementations, for example, but
prolog is not powerful enough to do this particular job. Some ancestors of
Maude may also be able to handle the job, and I may use those if the need
arises.

RW>Could you give us an example of what an ASML test might
RW>look like and how it would integrate into a program
RW>being tested?

http://research.microsoft.com/fse/asml/samples/ gives a good idea of what
an ASML specification looks like. Essentially, the IDE-style interface
that would probably be provided is a basic text editor along with some
functions that allow you to generate test cases from the specification,
and further to run all the tests against a specified program and collect
the results. I will have to find out from the ASML authors how their
manuals can be republished in a more usable format than .doc. The language
itself is very simple to understand and read; the most important issue to
explain in its use is how to write a specification in order to ennumerate
all the important test cases.

One thing that the Microsoft tools also do for you which naturally carries
over is the use of xml-formatted output of the test runs. I'll see about
any features that use this within the IDE. There's also the possibility of
formatting the actual specification in XML, but I'm not sure how much of
an advantage that would give. In any case, it would require access to the
internals of whatever logic engine I am using, to side-step the normal
parser.

RW>Testing is one of the areas that needs a lot of work.
RW>I've put together a couple of unit-testing frameworks,
RW>for testing the runtime, compiler, and library.  These
RW>frameworks are still in early days.
RW>
RW>Note: I can only speak for DotGNU Portable.NET.  I am
RW>not familiar with the testing requirements of other
RW>DotGNU components.

Alright, in that case, I won't be stepping on someone's feet, so to speak.
When the time comes, I'll try to work with people to convert their tests
into ASML. Since it provides additional automation in addition to being a
good documentation tool (reading the spec helps you read the program),
this should help out and may even uncover some rare bugs.

RW>> Keep in mind that I have used various
RW>> specification languages before, but have not developed under Windows in a
RW>> while, so I have to come up to speed on the specific issues.
RW>
RW>Not having developed under Windows is fine with us. :-)
RW>We do most of our development under GNU/Linux or other
RW>Unix clones.
RW>
RW>Cheers,
RW>Rhys.

Alright, thanks for your time. I'll respond again when I have a basic
system running and have the issues worked out to convert and re-publish
ASML's documents as HTML. I'll work with the authors to see how the
automated testing systems can be made as well.

Thanks,
Brian
~