On Wed, May 4, 2011 at 10:58 AM, Eric Niebler <eric@boostpro.com> wrote:
(cross-posting to the Proto list and cc'ing Hartmut.)
On 5/2/2011 6:18 PM, Thomas Heller wrote:
On Mon, May 2, 2011 at 12:54 PM, Eric Niebler <eric.niebler@gmail.com> wrote:
Phoenix is changing the following fundamental constants:
BOOST_PROTO_MAX_ARITY BOOST_MPL_LIMIT_METAFUNCTION_ARITY BOOST_PROTO_MAX_LOGICAL_ARITY BOOST_RESULT_OF_NUM_ARGS
IMO, Phoenix shouldn't be touching these. It should work as best it can with the default values. Users who are so inclined can change them.
Eric, This problem is well known. As of now I have no clue how to fix it properly.
Let me sketch why i changed these constants: 1) Phoenix V2 has a composite limit of 10: This is equivalent to the number of child expressions a expression can hold. This is controlled by BOOST_PROTO_MAX_ARITY for the number of template arguments for proto::expr and proto::basic_expr 2) Boost.Bind can take up to 10 parameters in the call to boost::bind
It's still not clear to me why you're changing BOOST_MPL_LIMIT_METAFUNCTION_ARITY and BOOST_PROTO_MAX_LOGICAL_ARITY.
BOOST_MPL_LIMIT_METAFUNCTION_ARITY: ./boost/proto/matches.hpp:56:8: error: #error BOOST_MPL_LIMIT_METAFUNCTION_ARITY must be at least as large as BOOST_PROTO_MAX_ARITY and BOOST_PROTO_MAX_LOGICAL_ARITY: ./boost/proto/proto_fwd.hpp:326: error: provided for ‘template<class G0, class G1, class G2, class G3, class G4, class G5, class G6, class G7> struct boost::proto::and_’ But i guess this can be fixed by simply splitting the call to proto::and_ ....