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| <a name="phoenix.starter_kit.composites.lazy_statements"></a><a class="link" href="lazy_statements.html" title="Lazy Statements">Lazy |
| Statements</a> |
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| <p> |
| Lazy statements? Sure. There are lazy versions of the C++ statements we |
| all know and love. For example: |
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| <pre class="programlisting"><span class="identifier">if_</span><span class="special">(</span><span class="identifier">arg1</span> <span class="special">></span> <span class="number">5</span><span class="special">)</span> |
| <span class="special">[</span> |
| <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="identifier">arg1</span> |
| <span class="special">]</span> |
| </pre> |
| <p> |
| Say, for example, we wish to print all the elements that are greater than |
| 5 (separated by a comma) in a vector. Here's how we write it: |
| </p> |
| <pre class="programlisting"><span class="identifier">std</span><span class="special">::</span><span class="identifier">for_each</span><span class="special">(</span><span class="identifier">v</span><span class="special">.</span><span class="identifier">begin</span><span class="special">(),</span> <span class="identifier">v</span><span class="special">.</span><span class="identifier">end</span><span class="special">(),</span> |
| <span class="identifier">if_</span><span class="special">(</span><span class="identifier">arg1</span> <span class="special">></span> <span class="number">5</span><span class="special">)</span> |
| <span class="special">[</span> |
| <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="identifier">arg1</span> <span class="special"><<</span> <span class="string">", "</span> |
| <span class="special">]</span> |
| <span class="special">);</span> |
| </pre> |
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| (See <a href="../../../../../example/if.cpp" target="_top">if.cpp</a>) |
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| <span class="inlinemediaobject"><img src="../../../images/tip.png" alt="tip"></span> Learn more about statements <a class="link" href="../../modules/statement.html" title="Statement">here.</a> |
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| <td align="right"><div class="copyright-footer">Copyright © 2002-2005, 2010 Joel de Guzman, Dan Marsden, Thomas Heller<p> |
| Distributed under the Boost Software License, Version 1.0. (See accompanying |
| 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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