"Arkadiy Vertleyb" <vertleyb@hotmail.com> writes:
"David Abrahams" <dave@boost-consulting.com> wrote
"Andrei Alexandrescu (See Website For Email)" <SeeWebsiteForEmail@moderncppdesign.com> writes:
1. Start from the Boost implementation of the C++ preprocessor, and add sane features to it. Keep the old preprocessor features as deprecated.
That one's a possibility. I personally would not want to solve these problems in the preprocessor layer because I want better integration with the rest of the language than that approach can offer. Others may feel differently, of course.
A better integration is not necessarily a good thing -- it's too restrictive. Something like FOREACH, for example (let's pay a tribute to the subject of this discussion), would not be possible in a well-integrated system
Sure it would.
-- the piece of code it generates is not, by itself, a valid fragment of a C++ program.
That doesn't matter. One possible implementation would be (in a made-up lisp-like language extension): [defmacro foreach [declaration *block] ...] where a parameter called *whatever is expected to be a block of code that syntactically follows the macro invocation. Would you (obviously) want to be able to do that? for example: [defmacro lambda [decl-list *block] ...] for lambda(int x, int y) { whatever }
So a totally independent code generation layer does have its advantages (at least it's more flexible).
That's true. But for that kind of flexibility, we have the PP already ;-) -- Dave Abrahams Boost Consulting www.boost-consulting.com