Hi all, I've been trying out boost::any in a messaging system to package up function arguments. A message call is basically Message::Call(std::vectorboost::any& args) { try ...a few any_cast<..> ...fire the actual function... catch ...etc } It's all good, except for one niggling problem. Say I have a double-precision value that I need changed inside the message, so it needs to be passed as a double* or a double& in an argument. The problem is, if I create a double& inside a boost::any, it doesn't point to the right memory location once I'm inside the message, and it looks like it's copying the original dereferenced value and giving me a reference to the copy. If I create a double* inside a boost::any, I get a new pointer inside the message like the reference, but because the pointer target is correct everything works. The code looks like this: ... ... std::vectorboost::any args; double d = 1.5; double* dptr = &d; msgargs.push_back(dptr);//works fine... double& dref = d; msgargs.push_back(dref);//seems to copy d instead of a reference to d... ... msg->Call(args); ... I can live with this, I just have to pass "large" objects by pointer so they don't get copied. BUT: Can anyone tell me why references are creating a copy of the original and not a copy of the reference, or how I could avoid the copying? Or am I doing something dumb? Damien