Alexander Nasonov > Eric Friedman wrote: > > But suppose I have a variant v3, with content of a different type (call it > > T3). Then the assignment v1 = v3 is far more complicated (we can't use > > T1::operator=) and, without double storage, far more dangerous. The single > > storage implementation behaves as follows: > > > > destroy v1 content > > copy v3 content into v1 > > Assuming that memcpy to new location followed by memcpy back to original > allocation is safe, you would do it using two additional storages local to > operator= function. Let's call them local1 and local2. [snip]
If I understand you correctly, earlier versions of variant did precisely what you describe. Unfortunately, the "assumption" you make is false in general. See http://aspn.activestate.com/ASPN/Mail/Message/boost/1311813. Eric _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost
