Re: [boost] [smart_ptr] enable_shared_from_this enhancement (patch)

From: Peter Dimov (pdimov_at_[hidden])
Date: 2008-03-20 11:25:57

Frank Mori Hess wrote:

> On Wednesday 19 March 2008 17:41 pm, Peter Dimov wrote:
>> What is the purpose of owned()?
>
> It indicates whether the object has had ownership passed to a
> shared_ptr yet. I don't have a strong justification on why it needs
> to be public, maybe it would be useful for debugging/diagnostic
> purposes.

It's better to omit the owned() accessor unless/until we have a use case for 
it.

> Attached is a test for the new functionality.

Looks good. In:

    {
        boost::weak_ptr<X> early_weak_px;
        {
            boost::shared_ptr<X> early_px;
            X x( 0, &early_px );
            boost::weak_ptr<X> early_weak_px = early_px;
            early_px.reset();
            BOOST_TEST( early_weak_px.expired() == false );
            BOOST_TEST( X::instances == 1 );
        }
        BOOST_TEST( early_weak_px.expired() );
    }

you probably didn't want to redeclare early_weak_px inside the {} block 
though.

As a minor stylistic issue, I'd prefer !expired() instead of expired() == 
false.

You might want to add tests for ownership sharing, !( early_px < px ) && 
!( px < early_px ).

One final question, in:

        BOOST_TEST( early_px.use_count() > 0 );

what does use_count() return? 2? Do we want to test against 2 directly, or 
are we to leave the initial use count unspecified?

Do you have SVN write access?