Johan Torp wrote:
Loïc Joly-2 wrote:
I was wondering whether there was any plan to implement a unique_ptr in boost, that would replace scoped_ptr, and would default to scoped_ptr on compilers lacking move semantic?
While std::unique_ptr and std::shared_ptr together cover a lot of functionality, I don't think boost::scoped_ptr should be changed or removed.
In some sense, scoped_ptr provides better static guarantees than unique_ptr. If you see a scoped_ptr declared at function scope you can be sure that it is deallocated when the function exits (unless someone abuses it with get()+reset(0)). A unique_ptr might transfer it ownership elsewhere.
So scoped_ptr's type tells us something and there is probably lots of code out there which wants to convey this information. Therefor we shouldn't change it's semantics. Also, scoped_ptr and auto_ptr are more lightweight since they do not have the extra level of indirection that a custom deleter requires.
Strongly agree. Many of my uses of scoped_ptr are in industrial code that will be maintained for years or even decades by programmers with very limited familiarity with the code involved. scoped_ptr communicates both to the maintainer and the compiler that ownership is never transfered. That is critical enough to justify a separate type, even though in other respects it is the same as unique_ptr. --Beman