Joel de Guzman wrote:
David Abrahams wrote:
Joel de Guzman wrote:
Yep. Another feature that makes backward compatibility imperfect. There's no sense in supporting that feature when Phoenix uses result_of and BOOST_TYPEOF.
Can you explain how Phoenix uses these facilities together?
You should ask Eric. He did that part when he ported it to proto. Phoenix used to have its own return type deduction which was a very primitive rendition of BOOST_TYPEOF using the sizeof trick I hacked a long time ago. Eric switched to result_of and BOOST_TYPEOF.
The Phoenix/Proto port in (Phoenix v3) uses BOOST_TYPEOF to deduce the the type of expressions involving operators, with the exception of the function call operator. For the function call operator, Phoenix v3 uses result_of to calculate the return type. To extend Phoenix v3 with a lazy function, your function object must conform to the result_of protocol. Phoenix lambda expressions are themselves function objects and conform to the result_of protocol. This is true for the (still immature) Phoenix v3. Phoenix v2 uses its own protocols. -- Eric Niebler BoostPro Computing http://www.boostpro.com