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| <div class="section" id="inserter"> |
| <h1><a class="toc-backref" href="./algorithms-concepts.html#id1462">Inserter</a></h1> |
| <div class="section" id="id454"> |
| <h3><a class="subsection-title" href="#description" name="description">Description</a></h3> |
| <p>An <a class="reference internal" href="./inserter.html">Inserter</a> is a compile-time substitute for STL <a class="reference external" href="http://www.sgi.com/tech/stl/OutputIterator.html" target="_top">Output Iterator</a>. |
| Under the hood, it's simply a type holding |
| two entities: a <em>state</em> and an <em>operation</em>. When passed to a |
| <a class="reference internal" href="./transformation-algorithms.html">transformation algorithm</a>, the inserter's binary operation is |
| invoked for every element that would normally be written into the |
| output iterator, with the element itself (as the second |
| argument) and the result of the previous operation's invocation — or, |
| for the very first element, the inserter's initial state.</p> |
| <p>Technically, instead of taking a single inserter parameter, |
| <a class="reference internal" href="./transformation-algorithms.html">transformation algorithms</a> could accept the state and the "output" |
| operation separately. Grouping these in a single parameter entity, |
| however, brings the algorithms semantically and syntactically closer to |
| their STL counterparts, significantly simplifying many of the common |
| use cases.</p> |
| </div> |
| <div class="section" id="valid-expressions"> |
| <h3>Valid expressions</h3> |
| <p>In the following table and subsequent specifications, <tt class="literal"><span class="pre">in</span></tt> is a model of <a class="reference internal" href="./inserter.html">Inserter</a>.</p> |
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| <col width="57%" /> |
| </colgroup> |
| <thead valign="bottom"> |
| <tr><th class="head">Expression</th> |
| <th class="head">Type</th> |
| </tr> |
| </thead> |
| <tbody valign="top"> |
| <tr><td><tt class="literal"><span class="pre">in::state</span></tt></td> |
| <td>Any type</td> |
| </tr> |
| <tr><td><tt class="literal"><span class="pre">in::operation</span></tt></td> |
| <td>Binary <a class="reference internal" href="./lambda-expression.html">Lambda Expression</a></td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| <div class="section" id="id455"> |
| <h3><a class="subsection-title" href="#expression-semantics" name="expression-semantics">Expression semantics</a></h3> |
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| <colgroup> |
| <col width="35%" /> |
| <col width="65%" /> |
| </colgroup> |
| <thead valign="bottom"> |
| <tr><th class="head">Expression</th> |
| <th class="head">Semantics</th> |
| </tr> |
| </thead> |
| <tbody valign="top"> |
| <tr><td><tt class="literal"><span class="pre">in::state</span></tt></td> |
| <td>The inserter's initial state.</td> |
| </tr> |
| <tr><td><tt class="literal"><span class="pre">in::operation</span></tt></td> |
| <td>The inserter's "output" operation.</td> |
| </tr> |
| </tbody> |
| </table> |
| </div> |
| <div class="section" id="id456"> |
| <h3><a class="subsection-title" href="#example" name="example">Example</a></h3> |
| <pre class="literal-block"> |
| typedef <a href="./transform.html" class="identifier">transform</a>< |
| <a href="./range-c.html" class="identifier">range_c</a><int,0,10> |
| , <a href="./plus.html" class="identifier">plus</a><<a href="./placeholders.html" class="identifier">_1</a>,<a href="./placeholders.html" class="identifier">_1</a>> |
| , <a href="./back-inserter.html" class="identifier">back_inserter</a>< vector0<> > |
| >::type result; |
| </pre> |
| </div> |
| <div class="section" id="id457"> |
| <h3><a class="subsection-title" href="#models" name="models">Models</a></h3> |
| <ul class="simple"> |
| <li><a class="reference internal" href="./inserter-class.html">inserter (class)</a></li> |
| <li><a class="reference internal" href="./front-inserter.html">front_inserter</a></li> |
| <li><a class="reference internal" href="./back-inserter.html">back_inserter</a></li> |
| </ul> |
| </div> |
| <div class="section" id="id458"> |
| <h3><a class="subsection-title" href="#see-also" name="see-also">See also</a></h3> |
| <p><a class="reference internal" href="./algorithms.html">Algorithms</a>, <a class="reference internal" href="./transformation-algorithms.html">Transformation Algorithms</a>, <a class="reference internal" href="./inserter-class.html">inserter (class)</a>, <a class="reference internal" href="./front-inserter.html">front_inserter</a>, <a class="reference internal" href="./back-inserter.html">back_inserter</a></p> |
| <!-- Algorithms/Concepts//Reversible Algorithm --> |
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| <td><div class="copyright-footer"><div class="copyright">Copyright © 2001-2009 Aleksey Gurtovoy and David Abrahams</div> |
| Distributed under the Boost Software License, Version 1.0. (See accompanying |
| file LICENSE_1_0.txt or copy at <a class="reference external" href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)</div></td></tr></table></body> |
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