Eric Niebler-3 wrote
I'm considering taking on as a side project the unification of the bind and phoenix placeholders, a perennial source of confusion and annoyance.
Bind should really not define _1, ... into the unamed namespace (IMO, this should be fixed in future Boost releases even if it will of course brake backward compatibility and existing code -- users can easily fix their existing code with using namespace boost::bind...). A part from that, why are Bind's placeholder confusing?
I hesitate before beginning because it necessarily introduces some complexity into boost.bind, a very small, simple, and light-weight library. In particular, the unification would:
1) Cause boost.bind to depend on boost.proto. (I would do what I could to keep that dependency as slight as possible.) 2) Could not be supported on all platforms; e.g. not on borland or (gcc < 4) where the placeholders are actually static inline functions(!). (Peter, is this an ODR thing?) 3) Would introduce Phoenix behaviors into Bind, insofar as _1 is a lambda such that _1(42) evaluates to 42.
Would it also complicate Bind compile-time errors?
At this point, it's not obvious to me that the benefits outweigh the costs. Opinions? Peter, I'd especially like to hear your thoughts.
What are the benefits of the unification? Thanks a lot. --Lorenzo -- View this message in context: http://boost.2283326.n4.nabble.com/bind-phoenix-unified-placeholders-yea-or-... Sent from the Boost - Dev mailing list archive at Nabble.com.