Joel de Guzman <joel@boost-consulting.com> writes:
Tobias Schwinger wrote:
Joel de Guzman wrote:
Tobias Schwinger wrote:
5. BTW...
I found it surprising that "iter->second" didn't work in place of "(*iter).second" (see lines 456, 485)...
This is tough. operator-> is required to be a member function. Unfortunately, that would also mean that the type dereferenced should also be known at compile time. This will ultimately break the MPL requirement that an iterator pointing at the *end* should not be dereferenced-- that's what will happen by the very act of computing the operator->'s return type.
I don't buy that argument. The past-the-end-iterator has a different type from all the others, and since it's not dereferenceable anyway, it doesn't need to have an operator->. Furthermore,
Unfortunately for Fusion iterators, I can't find a suitable workaround to enable operator-> return type deduction only when appropriate. In general, an iterator does not know if it is at the end.
That part seems strange to me. It certainly could know whether it's at the end, I think. -- Dave Abrahams Boost Consulting www.boost-consulting.com