On 09/28/2010 12:09 PM, Wayne Stambaugh wrote: > On 9/28/2010 12:43 PM, Dick Hollenbeck wrote: > >> >>> I probably would never personally use shared_ptr because in my mind it >>> is slightly beyond what an average C++ programmer uses on a day to day >>> basis, and it obscures the clear notion of "object ownership". >>> >>> I have never (I am old, this is a long long time, and countless lines of >>> code) been in a position where I could not assign object ownership >>> clearly to one container over another. If ever this became obscure, I >>> would probably backup and take another look. >>> >>> Object ownership is something to keep one's eye on. >>> >>> >>> Dick >>> >>> >> >> This was an opinion I expressed about shared_ptr, which hopes to relieve >> me of having to think clearly about object ownership. I have no problem >> thinking about object ownership, so I have this opinion about >> shared_ptr. IMO, shared_ptr is a solution without a sufficiently large >> problem. Managing object ownership is not a significantly difficult >> design responsibility, and has always been part of C/C++ programming. >> >> >> I don't feel the same way about auto_ptr, which is *one* reasonable way >> to deal with heap allocated objects in the face of exceptions. If no >> exceptions can occur, auto_ptr is not useful. If exceptions, then this >> is a sufficiently large problem to justify auto_ptr, but it is not the >> only solution. auto_ptr is one reasonable and simple solution. Another >> one that can also work is to simply stash the pointer soon after heap >> instantiation into the object's eventual owner, and then the problem >> gets moved to the owner. When the owner's destructor gets called, it >> deletes the newly instantiated owned object. Either solution is better >> than simply leaving the pointer on the heap and not copying it to the >> owner and not using auto_ptr, and then experiencing a thrown exception >> in that function that leaves the object exposed to a memory leak. >> >> >> Just wanted to clarify: >> >> auto_ptr: good sometimes, >> if you cannot copy pointer to the eventual owner soon enough, >> >> shared_ptr: not worth the cost. >> > Dick, > > I have already changed my code to not use shared_ptr. It isn't quite as > clean, > but it is close. I just have a bit more validation to do before I commit the > changes. This also means that I will not be changing the included boost > headers. > > Wayne >
Way cool. Looking forward to self documenting library files dude. WRT my last message, mostly I was trying to give auto_ptr a green light when needed, and to narrow the expression of my concern to shared_ptr. But I had also previously said I would yield to your considerable experience and judgment. Dick _______________________________________________ Mailing list: https://launchpad.net/~kicad-developers Post to : [email protected] Unsubscribe : https://launchpad.net/~kicad-developers More help : https://help.launchpad.net/ListHelp
