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Merge branch 'move-alias' of https://github.com/uecasm/smart_ptr into develop

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This commit is contained in:
Peter Dimov
2016-04-13 13:29:50 +03:00
parent 427124543b 05d5a4e9a0
commit cd8de9d4a6
4 changed files with 126 additions and 0 deletions
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8
include/boost/smart_ptr/shared_ptr.hpp
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@ -642,6 +642,14 @@ public:
return *this;
}
// aliasing move
template<class Y>
shared_ptr( shared_ptr<Y> && r, element_type * p ) BOOST_NOEXCEPT : px( p ), pn()
{
pn.swap( r.pn );
r.px = 0;
}
#endif
#if !defined( BOOST_NO_CXX11_NULLPTR )

12
shared_ptr.htm
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@ -139,6 +139,8 @@ void bad()
template&lt;class Y&gt; <a href="#aliasing_constructor" >shared_ptr</a>(shared_ptr&lt;Y&gt; const &amp; r, element_type * p); // never throws
template&lt;class Y&gt; <a href="#aliasing_move_constructor" >shared_ptr</a>(shared_ptr&lt;Y&gt; &amp;&amp; r, element_type * p); // never throws
template&lt;class Y&gt; explicit <a href="#weak_ptr_constructor" >shared_ptr</a>(<a href="weak_ptr.htm" >weak_ptr</a>&lt;Y&gt; const &amp; r);
template&lt;class Y&gt; explicit <a href="#auto_ptr_constructor" >shared_ptr</a>(std::auto_ptr&lt;Y&gt; &amp; r);
@ -352,6 +354,16 @@ template&lt;class Y&gt; shared_ptr(shared_ptr&lt;Y&gt; &amp;&amp; r); // never t
<p><b>Postconditions:</b> <code>get() == p &amp;&amp; use_count() == r.use_count()</code>.</p>
<p><b>Throws:</b> nothing.</p>
</blockquote>
<h3 id="aliasing_move_constructor">aliasing move constructor</h3>
<pre>template&lt;class Y&gt; shared_ptr(shared_ptr&lt;Y&gt; &amp;&amp; r, element_type * p); // never throws</pre>
<blockquote>
<p>
<b>Effects:</b> Move-constructs a <code>shared_ptr</code> from <code>r</code>, while
storing <code>p</code> instead.
</p>
<p><b>Postconditions:</b> <code>get() == p</code> and <code>use_count()</code> equals the old count of <code>r</code>. <code>r</code> is <em>empty</em> and <code>r.get() == 0</code>.</p>
<p><b>Throws:</b> nothing.</p>
</blockquote>
<h3 id="weak_ptr_constructor">weak_ptr constructor</h3>
<pre>template&lt;class Y&gt; explicit shared_ptr(<a href="weak_ptr.htm" >weak_ptr</a>&lt;Y&gt; const &amp; r);</pre>
<blockquote>

1
test/Jamfile.v2
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@ -34,6 +34,7 @@ import testing ;
[ run shared_ptr_alias_test.cpp ]
[ run shared_ptr_rv_test.cpp ]
[ run shared_ptr_move_test.cpp ]
[ run shared_ptr_alias_move_test.cpp ]
[ compile-fail shared_ptr_pv_fail.cpp ]
[ run sp_unary_addr_test.cpp ]
[ compile-fail scoped_ptr_eq_fail.cpp ]

105
test/shared_ptr_alias_move_test.cpp Normal file
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@ -0,0 +1,105 @@
#include <boost/config.hpp>
// shared_ptr_alias_move_test.cpp
//
// Copyright (c) 2007 Peter Dimov
//
// Distributed under the Boost Software License, Version 1.0. (See
// accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
#include <boost/detail/lightweight_test.hpp>
#include <boost/shared_ptr.hpp>
#include <utility>
#if !defined( BOOST_NO_CXX11_RVALUE_REFERENCES )
struct X
{
static long instances;
int v_;
explicit X( int v ): v_( v )
{
++instances;
}
~X()
{
v_ = 0;
--instances;
}
private:
X( X const & );
X & operator=( X const & );
};
long X::instances = 0;
int main()
{
BOOST_TEST( X::instances == 0 );
{
boost::shared_ptr< X > p( new X( 5 ) );
BOOST_TEST( X::instances == 1 );
BOOST_TEST( p.unique() );
BOOST_TEST( p->v_ == 5 );
boost::shared_ptr< X > p2( std::move( p ), p.get() );
BOOST_TEST( X::instances == 1 );
BOOST_TEST( p.get() == 0 );
BOOST_TEST( p2.unique() );
BOOST_TEST( p2->v_ == 5 );
boost::shared_ptr< int const > p3( std::move( p2 ), &p2->v_ );
BOOST_TEST( X::instances == 1 );
BOOST_TEST( p2.get() == 0 );
BOOST_TEST( p3.unique() );
BOOST_TEST( *p3 == 5 );
p3.reset();
BOOST_TEST( X::instances == 0 );
}
{
boost::shared_ptr< X > p( new X( 5 ) );
BOOST_TEST( X::instances == 1 );
BOOST_TEST( p.unique() );
BOOST_TEST( p->v_ == 5 );
{
boost::shared_ptr< X > p2(p);
BOOST_TEST( X::instances == 1 );
BOOST_TEST( p.get() == p2.get() );
BOOST_TEST( p.use_count() == 2 );
BOOST_TEST( p2.use_count() == 2 );
boost::shared_ptr< int const > p3( std::move( p2 ), &p2->v_ );
BOOST_TEST( X::instances == 1 );
BOOST_TEST( p.use_count() == 2 );
BOOST_TEST( p2.use_count() == 0 );
BOOST_TEST( p2.get() == 0 );
BOOST_TEST( p3.use_count() == 2 );
BOOST_TEST( p3.get() == &p->v_ );
}
BOOST_TEST( X::instances == 1 );
BOOST_TEST( p.unique() );
BOOST_TEST( p->v_ == 5 );
}
return boost::report_errors();
}
#else // defined( BOOST_NO_CXX11_RVALUE_REFERENCES )
int main()
{
return 0;
}
#endif