Otto Skrove Bagge wrote:

Nicolas Despres <despre_n@lrde.epita.fr> writes:

...

Hello,

We met each other at the fifth Stratego Users Days. I'm part of the Transformers team. We try to find a way to bridge the gap between Codeboost and Transformers. I mean, we think about writing a stratego filter to convert Transformers AST to Codeboost AST. Thus, we could glue Transformers front-end with Codeboost back-end.

Transformers release 0.1 is available on the web at http://www.lrde.epita.fr/cgi-bin/twiki/view/Projects/TransformersReleases

Have you planed a next release for CodeBoost soon ?

Yes, there is a new release, but it has not been annouced yet (since there really aren't any external users to announce it to, I haven't bothered). You can get it at http://download.codeboost.org/codeboost/codeboost-0.3.0.tar.gz

The subversion repository is also publicly available (svn checkout https://svn.cs.uu.nl:12443/repos/codeboost/trunk)

I had a look at Transformers a while ago, and I think it would be a great idea to have a bridge between Transformers and CodeBoost (especially if some of you guys are willing to write it...). I'm currently redesigning the abstract syntax, so it may be a waste of time to write a converter for the 3.0 AST. However, I noticed that your abstract syntax seems to follow the standard grammar quite closely; for example, it preserves the extra productions used for operator precedence. A good starting point might be to (design and) convert to an intermediate form which doesn't have these 'unnecessary' constructors. I believe it would then be easy to convert to CodeBoost's format (whatever it might end up looking like), and perhaps also interface with other C++ transformation tools.

The 3.0 abstract syntax is poorly documented. There is a bit of documentation in my thesis (available from the CodeBoost web page), and some recent changes are explained in the NEWS file. I'm trying to do a better job with the new and improved version. Note that while we in earlier versions of CodeBoost considered it important to preserve as much syntactic information as possible (e.g., whether the branches of an 'if' are compound statements or not, or whether some variables are declared in a single declaration (int a,b;) or in a sequence of declarations (int a; int b;)), we no longer feel this is important. This means that the CodeBoost abstract syntax is more like a high-level intermediate than an abstract representation of C++.

By the way, I did some experiments with Transformers on the Sophus library code (the code CodeBoost is designed to optimise), but I encountered problems with ambiguities (which was kind of expected, since some type information was missing). Also, it seemed to be a bit too slow to be usable for us at the moment. I expect both problems can be solved without too much trouble.

-otto

-- Nicolas Desprès nicolas.despres@lrde.epita.fr