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  26. <div class="titlepage"><div><div><h3 class="title">
  27. <a name="boost_typetraits.reference.is_nothrow_move_assignable"></a><a class="link" href="is_nothrow_move_assignable.html" title="is_nothrow_move_assignable">is_nothrow_move_assignable</a>
  28. </h3></div></div></div>
  29. <pre class="programlisting"><span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">class</span> <span class="identifier">T</span><span class="special">&gt;</span>
  30. <span class="keyword">struct</span> <span class="identifier">is_nothrow_move_assignable</span> <span class="special">:</span> <span class="keyword">public</span> <em class="replaceable"><code><a class="link" href="integral_constant.html" title="integral_constant">true_type</a>-or-<a class="link" href="integral_constant.html" title="integral_constant">false_type</a></code></em> <span class="special">{};</span>
  31. </pre>
  32. <p>
  33. <span class="bold"><strong>Inherits:</strong></span> If <code class="computeroutput"><span class="identifier">T</span></code>
  34. is a (possibly cv-qualified) type with a non-throwing move assignment-operator
  35. or a type without move assignment-operator but with non-throwing assignment-operator,
  36. then inherits from <a class="link" href="integral_constant.html" title="integral_constant">true_type</a>,
  37. otherwise inherits from <a class="link" href="integral_constant.html" title="integral_constant">false_type</a>.
  38. Type <code class="computeroutput"><span class="identifier">T</span></code> must be a complete
  39. type.
  40. </p>
  41. <p>
  42. In other words, inherits from <a class="link" href="integral_constant.html" title="integral_constant">true_type</a>
  43. only if expression <code class="computeroutput"><span class="identifier">variable1</span> <span class="special">=</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">move</span><span class="special">(</span><span class="identifier">variable2</span><span class="special">)</span></code> won't throw (<code class="computeroutput"><span class="identifier">variable1</span></code>
  44. and <code class="computeroutput"><span class="identifier">variable2</span></code> are variables
  45. of type <code class="computeroutput"><span class="identifier">T</span></code>).
  46. </p>
  47. <p>
  48. <span class="bold"><strong>Compiler Compatibility:</strong></span> If the compiler
  49. does not support partial-specialization of class templates, then this template
  50. can not be used with function types.
  51. </p>
  52. <p>
  53. Without some (C++11 noexcept shall work correctly) help from the compiler,
  54. <code class="computeroutput"><span class="identifier">is_nothrow_move_assignable</span></code>
  55. will never report that a class or struct has a non-throwing assignment-operator;
  56. this is always safe, if possibly sub-optimal. Currently (June 2015) MSVC-12.0,
  57. Clang and GCC 4.7 have the necessary compiler support to ensure that this
  58. trait "just works".
  59. </p>
  60. <p>
  61. <span class="bold"><strong>Header:</strong></span> <code class="computeroutput"> <span class="preprocessor">#include</span>
  62. <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">type_traits</span><span class="special">/</span><span class="identifier">is_nothrow_move_assignable</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span></code>
  63. or <code class="computeroutput"> <span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">type_traits</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span></code>
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  69. Frederic Bron, Steve Cleary, Beman Dawes, Aleksey Gurtovoy, Howard Hinnant,
  70. Jesse Jones, Mat Marcus, Itay Maman, John Maddock, Alexander Nasonov, Thorsten
  71. Ottosen, Roman Perepelitsa, Robert Ramey, Jeremy Siek, Robert Stewart and Steven
  72. Watanabe<p>
  73. Distributed under the Boost Software License, Version 1.0. (See accompanying
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