On 2/26/06, Tobias Schwinger <tschwinger@neoscientists.org> wrote:
Peder Holt wrote:
In confix_parser_gen: Adding another level of indirection solves the problem: [...]
Now rule_parser_1_1 passes without problems.
Great!
Attached is a patch with this fix.
I applied the workaround to all functions in the CVS version of confix.hpp. Unfortunately the same trick won't help to get rid of the ICE in rule_parser_2_2 when applied to the subscript operator of spirit::parser (would've been too easy)...
I have looked at this, and this is a problem between VC7.1 and the way the typeof emulation works, as you showed in the simplified test-case. The problem lies in the use of the operator[] with function pointers. The only workaround for this problem that I have found, apart from rewriting the user code, is to separate the sizeof operation and the typedef. (like in the #if ! defined BOOM clause) Problem is, this has to be done inside a struct, and can not be made to emulate the BOOST_TYPEOF syntax. The proposed solution is then to add a new macro called something like: BOOST_TYPEOF_NESTED_TYPEDEF(name,expr) which looks roughly like this: struct name { //Twophase typeof using expr typedef resulting_type_calculated type; }; To access the type, you have to do a typedef typename name::type my_type; outside BOOST_TYPEOF_NESTED_TYPEDEF. Introducing this construct has two positive effects: 1. rule_parser_2_2 (and similar tests) pass. 2. In emulation mode, there is no longer any limit to the complexity of the types passed to BOOST_TYPEOF_NESTED_TYPEDEF. BOOST_TYPEOF_LIMIT_SIZE is no longer a limiting factor. The downside is the added complexity of the library. It also doesn't reflect any proposed C++ features. Is there any interest in adding this feature to the typeof library? Regards, Peder