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1 files changed, 47 insertions, 18 deletions
diff --git a/doc/html/unordered/compliance.html b/doc/html/unordered/compliance.html index 2244d560f1..8612841e22 100644 --- a/doc/html/unordered/compliance.html +++ b/doc/html/unordered/compliance.html @@ -2,7 +2,7 @@ <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> -<title>C++11 Compliance</title> +<title>Standard Compliance</title> <link rel="stylesheet" href="../../../doc/src/boostbook.css" type="text/css"> <meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> <link rel="home" href="../index.html" title="The Boost C++ Libraries BoostBook Documentation Subset"> @@ -25,14 +25,23 @@ </div> <div class="section"> <div class="titlepage"><div><div><h2 class="title" style="clear: both"> -<a name="unordered.compliance"></a><a class="link" href="compliance.html" title="C++11 Compliance">C++11 Compliance</a> +<a name="unordered.compliance"></a><a class="link" href="compliance.html" title="Standard Compliance">Standard Compliance</a> </h2></div></div></div> <div class="toc"><dl class="toc"> <dt><span class="section"><a href="compliance.html#unordered.compliance.move">Move emulation</a></span></dt> <dt><span class="section"><a href="compliance.html#unordered.compliance.allocator_compliance">Use of allocators</a></span></dt> -<dt><span class="section"><a href="compliance.html#unordered.compliance.pairs">Pairs</a></span></dt> +<dt><span class="section"><a href="compliance.html#unordered.compliance.construction">Construction/Destruction + using allocators</a></span></dt> +<dt><span class="section"><a href="compliance.html#unordered.compliance.pointer_traits">Pointer Traits</a></span></dt> +<dt><span class="section"><a href="compliance.html#unordered.compliance.pairs0">Pairs</a></span></dt> <dt><span class="section"><a href="compliance.html#unordered.compliance.misc">Miscellaneous</a></span></dt> </dl></div> +<p> + The intent of Boost.Unordered is to implement a close (but inperfect) implementation + of the C++17 standard, that will work with C++98 upwards. The wide compatibility + does mean some comprimises have to be made. With a compiler and library that + fully support C++11, the differences should be minor. + </p> <div class="section"> <div class="titlepage"><div><div><h3 class="title"> <a name="unordered.compliance.move"></a><a class="link" href="compliance.html#unordered.compliance.move" title="Move emulation">Move emulation</a> @@ -94,26 +103,46 @@ on some compilers and <code class="computeroutput"><span class="identifier">propagate_on_container_move_assignment</span></code> on others. </p> +</div> +<div class="section"> +<div class="titlepage"><div><div><h3 class="title"> +<a name="unordered.compliance.construction"></a><a class="link" href="compliance.html#unordered.compliance.construction" title="Construction/Destruction using allocators">Construction/Destruction + using allocators</a> +</h3></div></div></div> +<p> + The following support is required for full use of C++11 style construction/destruction: + </p> +<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> +<li class="listitem"> + Variadic templates. + </li> +<li class="listitem"> + Piecewise construction of <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span></code>. + </li> +<li class="listitem"> + Either <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">allocator_traits</span></code> or expression SFINAE. + </li> +</ul></div> <p> - The use of the allocator's construct and destruct methods might be a bit - surprising. Nodes are constructed and destructed using the allocator, but - the elements are stored in aligned space within the node and constructed - and destructed by calling the constructor and destructor directly. + This is detected using Boost.Config. The macro <code class="computeroutput"><span class="identifier">BOOST_UNORDERED_CXX11_CONSTRUCTION</span></code> + will be set to 1 if it is found, or 0 otherwise. </p> <p> - In C++11 the allocator's construct function has the signature: + When this is the case <code class="computeroutput"><span class="identifier">allocator_traits</span><span class="special">::</span><span class="identifier">construct</span></code> + and <code class="computeroutput"><span class="identifier">allocator_traits</span><span class="special">::</span><span class="identifier">destroy</span></code> will always be used, apart from + when piecewise constructing a <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span></code> + using <code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">tuple</span></code> (see <a class="link" href="compliance.html#unordered.compliance.pairs">below</a>), + but that should be easily avoided. </p> -<pre class="programlisting"><span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">U</span><span class="special">,</span> <span class="keyword">class</span><span class="special">...</span> <span class="identifier">Args</span><span class="special">></span> -<span class="keyword">void</span> <span class="identifier">construct</span><span class="special">(</span><span class="identifier">U</span><span class="special">*</span> <span class="identifier">p</span><span class="special">,</span> <span class="identifier">Args</span><span class="special">&&...</span> <span class="identifier">args</span><span class="special">);</span> -</pre> <p> - which supports calling <code class="computeroutput"><span class="identifier">construct</span></code> - for the contained object, but most existing allocators don't support this. - If member function detection was good enough then with old allocators it - would fall back to calling the element's constructor directly but in general, - detection isn't good enough to do this which is why Boost.Unordered just - calls the constructor directly every time. In most cases this will work okay. + When support is not available <code class="computeroutput"><span class="identifier">allocator_traits</span><span class="special">::</span><span class="identifier">construct</span></code> + and <code class="computeroutput"><span class="identifier">allocator_traits</span><span class="special">::</span><span class="identifier">destroy</span></code> are never called. </p> +</div> +<div class="section"> +<div class="titlepage"><div><div><h3 class="title"> +<a name="unordered.compliance.pointer_traits"></a><a class="link" href="compliance.html#unordered.compliance.pointer_traits" title="Pointer Traits">Pointer Traits</a> +</h3></div></div></div> <p> <code class="computeroutput"><span class="identifier">pointer_traits</span></code> aren't used. Instead, pointer types are obtained from rebound allocators, this can cause @@ -124,7 +153,7 @@ </div> <div class="section"> <div class="titlepage"><div><div><h3 class="title"> -<a name="unordered.compliance.pairs"></a><a class="link" href="compliance.html#unordered.compliance.pairs" title="Pairs">Pairs</a> +<a name="unordered.compliance.pairs0"></a><a name="unordered.compliance.pairs"></a><a class="link" href="compliance.html#unordered.compliance.pairs0" title="Pairs">Pairs</a> </h3></div></div></div> <p> Since the containers use <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">pair</span></code> |