Re: [boost] Smart Pointer Feature Model

From: Beman Dawes (beman_at_[hidden])
Date: 2000-07-13 14:28:09

Kevlin Henney wrote:

 > ...
 >> >>ownership      ( tightly-held    // scoped_ptr
 >> >>                | transferable    // auto_ptr
 >> >>                | shared          // shared_ptr, linked_ptr, etc.
 >> >>                | weak            // ??? weak_ptr
 >> >>                | copyable        // copy_ptr
 >> >
 >> >Also: 'unowned'.
 >>
 >>Hum... Is it still a smart pointer?  Could you explain a bit?
 >
 >Yup. Going back to square one (or should that be zero as it's C++?)
 >smart pointers are proxy objects that add management and access control
 >to a level of indirection, idiomatically appearing to support parts of
 >the built-in pointer protocol. A common application (and misconception)
 >is SPs for memory management. This is only one role that they can play:
 >checking, locking, loading, navigation, etc are others. Hence, most
 >iterators in the standard library are examples of smart pointers even
 >though they have no strong ownership semantics.

Ah! The light dawns. In Tokyo Robert Klarer was talking about trying to 
come up with a grand unification theory of pointers and iterators.  Sounds 
like you just did!  Now the trick is to try to fit them into the feature 
diagram.  Have to think about that...

 > ...
 >
 >>Is this a viable approach and in keeping with C&E?
 >
 >Don't know yet! But it sounds good.

Please do read the book; my guess is that several of us exploring the 
possibilities together will go a lot farther that solo flight.

--Beman