[Boost-users] Re: multi_index and VC70 problem

Hi Martin,

I haven't compiled your code, but I'm pretty confident the problem lies in the following: instead of

composite_key< BOOST_MULTI_INDEX_MEMBER(tTest, int, x) ,BOOST_MULTI_INDEX_MEMBER(tTest, int, y) )

you should write

composite_key< tTest ,BOOST_MULTI_INDEX_MEMBER(tTest, int, x) ,BOOST_MULTI_INDEX_MEMBER(tTest, int, y) )

i.e. the first parameter of composite_key is the value to which the extractors are applied. Please let me know if that solves the issue.

That was a quick reply and you are correct. It is the first time I use composite keys and I followed the examples. My error was that I thought the first class argument in the examples meant the identity comparison. Looking at it now I understand how stupid that was.

Other than that, I'm always eager to get feedback from users of the lib, so if you have additional comments or suggestions please let me know.

I work a lot with databases and I often have the need to store table like information in RAM. I often have a structure like struct table_t { string key; std::vector subtable; }; The multi_index works perfectly for this. The only thing I am missing is a way to update the non-key elements in-place. Often my structures include subtables which means the copy can be expensive and I don't want to add member functions to update each member. Currently I do const_cast(itr->subtable).push_back(xxx); It would be nice if there was a macro or template that could do it in a safe way, i.e. ensure index isn't changed. nonkey(itr->subtable).push_back(xxx);