On 4/7/2011 6:57 AM, Nathan Crookston wrote:
On Wed, Apr 6, 2011 at 4:42 PM, Steven Watanabe<watanabesj@gmail.com> wrote:
I get errors too with 1.46.0. It looks like it's because transform_iterator doesn't use result_of. IIRC, this was fixed /very/ recently.
Phoenix v2 is tricky to use with transform due to result_of -- for one, there was the bug Steven mentioned with transform_iterator. For two, Phoenix v2's return type deduction mechanism is different than that used by result_of. Phoenix v3 uses result_of and should then be interoperable with boost::adaptors::transformed. For the time being it may be better to use boost::bind in this case.
Not quite true. That's a common misconception. Phoenix v2 *does* support result_of. It's just phoenix::function that does not support it due to legacy code and backward compat. As a matter of fact, I took Steven's code and changed the headers to that of V2 and it compiles: #include <boost/range/adaptor/transformed.hpp> #include <boost/spirit/include/phoenix_core.hpp> #include <boost/spirit/include/phoenix_bind.hpp> #include <vector> class A {}; class B { public: A a; }; class C { public: static B BFromA(const A& a) { return B(); } }; template<class T, class Range> T construct(const Range& r) { return T(boost::begin(r), boost::end(r)); } std::vector<B> CsFromBs(std::vector<B> bs) { return construct<std::vector<B> >(bs | boost::adaptors::transformed(boost::phoenix::bind(&C::BFromA, boost::phoenix::bind(&B::a, boost::phoenix::arg_names::arg1)))); } Regards, -- Joel de Guzman http://www.boostpro.com http://boost-spirit.com