[Boost-users] [bind] use with shared_ptr

From: Neal Coombes (nealc_at_[hidden])
Date: 2005-09-15 09:03:44

Bind is very convenient for use with shared_ptr:

struct C { void func() {} };
shared_ptr<C> c(new C);
bind(&C::func, c)();  // calls c->func()

However I've found a snag when trying to do function composition:

class A { shared_ptr<C> func() { return shared_ptr<C>(new C); } };
A a;
bind(&C::func, bind(&A::func, a)); // doesn't work, instead must:
bind(&C::func, bind(&get_pointer<B>, bind(&A::func, a)));

The fact that I can work around this is obviously a good thing.  But the 
work around is significantly less clear, especially when attempting to 
convince a development team that boost and bind are Good Things(tm) and 
they should be adopted.

Is it horribly difficult to make the simpler composition work (i.e. was 
it tried and impossible or simply overlooked)?

Thanks,
Neal