On Thu, Sep 2, 2010 at 6:55 PM, Florian Goujeon <florian.goujeon@42ndart.org> wrote:
 Dear Boosters,
I'd like to introduce to you the Scalpel library, a project on which I've worked during the last two years.
Scalpel is a C++ library. Its name stands for source code analysis, libre and portable library. It is still under development, but is a fairly advanced work in progress.
The purpose of this library is to produce a data structure which corresponds to the meaning (or semantics) of a given C++ source code. It reveals notions such as namespaces, classes, functions, variables, types, etc..
Some source code analyzers, like those used by syntax coloring and autocomplete modules which need to be fast, perform a superficial analysis. Unlike them, Scalpel aims to accomplish a strict and exhaustive analysis so that it could even be used as a compiler front-end. Actually, Scalpel is a compiler front-end, since it goes through the phases of preprocessing, syntax analysis and semantic analysis, just like every C++ compiler does. Maybe one day there will be a Scalpel-powered C++ compiler!
Besides, Scalpel's analysis depth will be adjustable in order to fit the needs of most programs. For example, it could be possible to disable the function body analysis for those who need to retrieve namespace and class members only.
The labor of C++ source code analysis is extremely complex. This is why having a library wholly devoted to it is a good thing.
Many programs could take advantage of such a library. Among them we can find modules for code editors, reverse-engineering tools, code audit software and many other CASE (Computer-Aided Software Engineering) tools that remain to be invented…
Having a good, open-source C++ parser library that could support such tools would be wonderful. However, I am going to be a stick-in-the-mud and propose that we already have such a library. Clang: http://clang.llvm.org/ Clang is an open-source C++ library developed under a Boost-compatible BSD-like license [1]. It's written completely in C++, and performs preprocessing, parsing, semantic analysis, and code generation for C/C++/Objective-C/Objective-C++ (+ OpenCL, if you have a supporting environment) on a variety of targets. It's designed as a set of reusable libraries, so that it can form the basis of tools, and includes support libraries for program indexing, source-to-source transformation, code completion, and static analysis (among others!). Clang already implements support for the entire C++98/03 language (except exported templates), and does so well enough that it can handle all of Boost [2]. For reference, check out the dgregor2/clang-darwin-2.8 column on today's Boost regression-test results: http://www.boost.org/development/tests/release/developer/summary.html where you'll see that Clang is passing nearly every Boost regression test on the release branch. Clang is supported both by industry [3] and by an awesome open-source community, which (as with Boost) makes for a great symbiotic relationship: industry provides the stability and focus needed to turn Clang into a production-quality C++ compiler, while the open-source community provides a wealth of ideas and vision that pushes Clang into new areas. For example, a group within the Clang community has taken it upon themselves to start implementing Microsoft-specific extensions to make Clang far easier to use on Windows. Writing a C++ parser/compiler requires years of full-time technical effort, and I strongly encourage you not to begin yet another open-source C++ parser. There are already two good open-source C++ compilers, GCC and Clang, and I'd strongly recommend working toward making one of those two projects better. As an added bonus, both compilers are at a stage where you can come into the community and work on the fun stuff (C++0x features, tools for C++ programmers, optimizations, etc.) rather than slog through the dull parts of C++ (initialization, name lookup, access control). - Doug, Clang C++ technical lead [1] Scalpel appears to be under an LGPL license, which is not Boost-compatible. [2] Clang hit this milestone back in May: http://blog.llvm.org/2010/05/clang-builds-boost.html [3] Apple has already shipped Clang as a C/Objective-C compiler (about a year ago). Apparently, several OpenCL implementations are also based on Clang (see http://en.wikipedia.org/wiki/OpenCL), and there has been significant interest from industry