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  26. <div class="titlepage"><div><div><h3 class="title">
  27. <a name="boost_typetraits.reference.is_polymorphic"></a><a class="link" href="is_polymorphic.html" title="is_polymorphic">is_polymorphic</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_polymorphic</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 T is a (possibly cv-qualified)
  34. polymorphic type then inherits from <a class="link" href="integral_constant.html" title="integral_constant">true_type</a>,
  35. otherwise inherits from <a class="link" href="integral_constant.html" title="integral_constant">false_type</a>.
  36. Type <code class="computeroutput"><span class="identifier">T</span></code> must be a complete
  37. type.
  38. </p>
  39. <p>
  40. <span class="bold"><strong>C++ Standard Reference:</strong></span> 10.3.
  41. </p>
  42. <p>
  43. <span class="bold"><strong>Compiler Compatibility:</strong></span> The implementation
  44. requires some knowledge of the compilers ABI, it does actually seem to work
  45. with the majority of compilers though.
  46. </p>
  47. <p>
  48. <span class="bold"><strong>Header:</strong></span> <code class="computeroutput"> <span class="preprocessor">#include</span>
  49. <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_polymorphic</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span></code>
  50. 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>
  51. </p>
  52. <p>
  53. <span class="bold"><strong>Examples:</strong></span>
  54. </p>
  55. <div class="blockquote"><blockquote class="blockquote"><p>
  56. Given: <code class="computeroutput"><span class="keyword">class</span> <span class="identifier">poly</span><span class="special">{</span> <span class="keyword">virtual</span> <span class="special">~</span><span class="identifier">poly</span><span class="special">();</span> <span class="special">};</span></code>
  57. </p></blockquote></div>
  58. <div class="blockquote"><blockquote class="blockquote"><p>
  59. <code class="computeroutput"><span class="identifier">is_polymorphic</span><span class="special">&lt;</span><span class="identifier">poly</span><span class="special">&gt;</span></code>
  60. inherits from <code class="computeroutput"><a class="link" href="integral_constant.html" title="integral_constant">true_type</a></code>.
  61. </p></blockquote></div>
  62. <div class="blockquote"><blockquote class="blockquote"><p>
  63. <code class="computeroutput"><span class="identifier">is_polymorphic</span><span class="special">&lt;</span><span class="identifier">poly</span> <span class="keyword">const</span><span class="special">&gt;::</span><span class="identifier">type</span></code>
  64. is the type <code class="computeroutput"><a class="link" href="integral_constant.html" title="integral_constant">true_type</a></code>.
  65. </p></blockquote></div>
  66. <div class="blockquote"><blockquote class="blockquote"><p>
  67. <code class="computeroutput"><span class="identifier">is_polymorphic</span><span class="special">&lt;</span><span class="identifier">poly</span><span class="special">&gt;::</span><span class="identifier">value</span></code> is an integral constant expression
  68. that evaluates to <span class="emphasis"><em>true</em></span>.
  69. </p></blockquote></div>
  70. <div class="blockquote"><blockquote class="blockquote"><p>
  71. <code class="computeroutput"><span class="identifier">is_polymorphic</span><span class="special">&lt;</span><span class="identifier">T</span><span class="special">&gt;::</span><span class="identifier">value_type</span></code> is the type <code class="computeroutput"><span class="keyword">bool</span></code>.
  72. </p></blockquote></div>
  73. </div>
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  77. Frederic Bron, Steve Cleary, Beman Dawes, Aleksey Gurtovoy, Howard Hinnant,
  78. Jesse Jones, Mat Marcus, Itay Maman, John Maddock, Alexander Nasonov, Thorsten
  79. Ottosen, Roman Perepelitsa, Robert Ramey, Jeremy Siek, Robert Stewart and Steven
  80. Watanabe<p>
  81. Distributed under the Boost Software License, Version 1.0. (See accompanying
  82. file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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