[boost] Re: Interest: Pointer Container Library

From: Dan W. (danw_at_[hidden])
Date: 2003-12-29 00:31:13

Sorry to post as new thread, I still haven't figured out how to reply to a 
thread...

 >> Would it be safer for push_back(), say, to take a smart pointer as input?

 >in some sense yes. You're thinking about giving the user a hint about the
 >ownership semantics. However,
 >since the user could also pass the address of a stack object to the smart
 >pointer, we have only
 >moved the problem. Knowing that the containers take ownership is really
 >neccesary to use the containers
 >properly; we can't protect against malice.

I just thought of another situation where where smart pointer input might 
be useful. Say I want two or more pointer containers to share ownership of 
some of the pointed to elements...
Example: A 3D game-engine where I keep objects into sorted containers along 
X, Y and Z coordinates. Or to make it more complex (and more realistic a 
situation) where I have multiple overlapping containers along each of the 
axes, where the multiple containers handle distinct orders of distance, and 
inversely proportional levels of detail. I may not want an object to be 
deleted until it has been dropped from all containers. Also, with 
boost::shared_ptr I can supply an alternate deleter functor. I haven't 
looked at your code very deeply yet, is there a similar capability built 
in, or would you consider it doable or useful?