> what i've really been wondering about for a while is > whether there are any considerations of static / compile-time introspection, > and if not, why. > It's nothing pressing, i'm just really curious and i haven't found anything > on it (besides the rare musings of other C++ users on this). > > Basically static introspection would allow meta-programming to take it a step > further; e.g. to use template-meta-programming to iterate at compile-time > through information about members of namespaces and classes. You would be > able to get their signatures/addresses/names/attributes/... and generate > code for them. > Use-cases would e.g. be: > * generation of bridging code (C++ ↔ script) > * various wrapper scenarios (forward/filter/... interfaces) > * runtime reflection for select code subsets > … for which currently separate pre-build steps (e.g. Qts moc), pre-processor > markup (say Boost Reflect), repetitive code etc. are necessary - so it's > either crude or requires specific toolchains.
This is definitely an active area of investigation in the Committee. There is a Reflection Study Group (a sub-group of the Committee which focuses on a particular area) which is tasked with investigating language and library extensions for compile-time and runtime reflection. The majority of the interest so far has been for compile-time reflection, but I believe some of the infrastructure for compile-time reflection will enable runtime reflection as well. The Reflection Study Group met in Chicago last week, and talked about a rough outline of the sorts of things C++ programmers would like to be able to do with reflection, from straightforward things like iterating over the members of a class at compile-time for purposes such as serialization and equality comparison, to more sophisticated things like synthesizing new types by transforming existing types. I believe the plan is to issue a call for proposals, with some guidance about the general direction that is desired, derived from that outline. The Study Group will then look at the proposals at future meetings and provide feedback, with the aim of converging towards a cohesive set of proposals to present to the Committee at large. Since this is a very broad area to explore, I believe the Study Group is initially interested particularly in proposals that provide infrastructure that compile-time reflection features can be built on top of. This should become more clear when the call for proposals is issued. Botond _______________________________________________ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
