[boost] Proposal: Efficient Pointers

From: Philippe A. Bouchard (philippeb_at_[hidden])
Date: 2002-07-15 21:31:43

Greeting,

    After a usefull discussion under comp.lang.c++ newsgroup I've made some
modifications to pointers I've already suggested.  I am proposing two
different pointers that emphasize efficienty:

mutable_ptr<>:
    - literally breaks some compiler assertions that prevents
std::auto_ptr<> from being easily copied;
    - is really beneficial for STL container self destructions - believe me;
    - copies are a lot easier to manage: work with secondary pure pointers
assignments;
    - member declarations identical to std::auto_ptr<>;
    - as fast as std::auto_ptr<>.

shared_ptr<>:
    - functionality is similar to boost::shared_ptr<> except:
        - reference counters are merged with instanciated objects:
            - operator new () is called once in the end (like
boost::shared_ptr<>);
            - the pointer is same size as sizeof(void *);
            - reference counters are not copied when assignments are called;
        - little drawback: assignments work only with other
fdi::shared_ptr<>
    - the only change from std::auto_ptr<> interface was that release() was
renamed to share();
    - faster than boost::shared_ptr<>.

A personnaly prefer using mptr<> and sptr<> because the code is easier to
read in one line.  I won't recommend macros but simply to rename classes.
One other thing: the fdi:: namespace is volatile.  I hope someone will share
the same vision of efficienty benefits I have.

Thank you,

Philippe A. Bouchard

begin 666 mutable_ptr.h
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`
end

begin 666 shared_ptr.h
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`
end

begin 666 testptr.cpp
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`
end