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| <div class="section" id="deref"> |
| <h1><a class="toc-backref" href="./iterator-metafunctions.html#id1458">deref</a></h1> |
| <div class="section" id="id437"> |
| <h3><a class="subsection-title" href="#synopsis" name="synopsis">Synopsis</a></h3> |
| <pre class="literal-block"> |
| template< |
| typename Iterator |
| > |
| struct <a href="./deref.html" class="identifier">deref</a> |
| { |
| typedef <em>unspecified</em> type; |
| }; |
| </pre> |
| </div> |
| <div class="section" id="id438"> |
| <h3><a class="subsection-title" href="#description" name="description">Description</a></h3> |
| <p>Dereferences an iterator.</p> |
| </div> |
| <div class="section" id="id439"> |
| <h3><a class="subsection-title" href="#header" name="header">Header</a></h3> |
| <pre class="literal-block"> |
| #include <<a href="../../../../boost/mpl/deref.hpp" class="header">boost/mpl/deref.hpp</a>> |
| </pre> |
| </div> |
| <div class="section" id="id440"> |
| <h3><a class="subsection-title" href="#parameters" name="parameters">Parameters</a></h3> |
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| <col width="35%" /> |
| <col width="45%" /> |
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| <thead valign="bottom"> |
| <tr><th class="head">Parameter</th> |
| <th class="head">Requirement</th> |
| <th class="head">Description</th> |
| </tr> |
| </thead> |
| <tbody valign="top"> |
| <tr><td><tt class="literal"><span class="pre">Iterator</span></tt></td> |
| <td><a class="reference internal" href="./forward-iterator.html">Forward Iterator</a></td> |
| <td>The iterator to dereference.</td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| <div class="section" id="id441"> |
| <h3><a class="subsection-title" href="#expression-semantics" name="expression-semantics">Expression semantics</a></h3> |
| <p>For any <a class="reference internal" href="./forward-iterator.html">Forward Iterator</a>s <tt class="literal"><span class="pre">iter</span></tt>:</p> |
| <pre class="literal-block"> |
| typedef <a href="./deref.html" class="identifier">deref</a><iter>::type t; |
| </pre> |
| <table class="docutils field-list" frame="void" rules="none"> |
| <col class="field-name" /> |
| <col class="field-body" /> |
| <tbody valign="top"> |
| <tr class="field"><th class="field-name">Return type:</th><td class="field-body"><p class="first">A type.</p> |
| </td> |
| </tr> |
| <tr class="field"><th class="field-name">Precondition:</th><td class="field-body"><p class="first"><tt class="literal"><span class="pre">iter</span></tt> is dereferenceable.</p> |
| </td> |
| </tr> |
| <tr class="field"><th class="field-name">Semantics:</th><td class="field-body"><p class="first"><tt class="literal"><span class="pre">t</span></tt> is identical to the element referenced by <tt class="literal"><span class="pre">iter</span></tt>. If <tt class="literal"><span class="pre">iter</span></tt> is |
| a user-defined iterator, the library-provided default implementation is |
| equivalent to</p> |
| <pre class="last literal-block"> |
| typedef iter::type t; |
| </pre> |
| </td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| <div class="section" id="id442"> |
| <h3><a class="subsection-title" href="#complexity" name="complexity">Complexity</a></h3> |
| <p>Amortized constant time.</p> |
| </div> |
| <div class="section" id="id443"> |
| <h3><a class="subsection-title" href="#example" name="example">Example</a></h3> |
| <pre class="literal-block"> |
| typedef <a href="./vector.html" class="identifier">vector</a><char,short,int,long> types; |
| typedef <a href="./begin.html" class="identifier">begin</a><types>::type iter; |
| |
| <a href="./assert.html" class="identifier">BOOST_MPL_ASSERT</a>(( is_same< <a href="./deref.html" class="identifier">deref</a><iter>::type, char > )); |
| </pre> |
| </div> |
| <div class="section" id="id444"> |
| <h3><a class="subsection-title" href="#see-also" name="see-also">See also</a></h3> |
| <p><a class="reference internal" href="./iterators.html">Iterators</a>, <a class="reference internal" href="./begin.html">begin</a> / <a class="reference internal" href="./end.html">end</a>, <a class="reference internal" href="./next.html">next</a></p> |
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