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| <div class="titlepage"><div><div><h3 class="title"> |
| <a name="boost_asio.reference.TimeTraits"></a><a class="link" href="TimeTraits.html" title="Time traits requirements">Time traits requirements</a> |
| </h3></div></div></div> |
| <p> |
| In the table below, <code class="computeroutput"><span class="identifier">X</span></code> denotes |
| a time traits class for time type <code class="computeroutput"><span class="identifier">Time</span></code>, |
| <code class="computeroutput"><span class="identifier">t</span></code>, <code class="computeroutput"><span class="identifier">t1</span></code>, |
| and <code class="computeroutput"><span class="identifier">t2</span></code> denote values of type |
| <code class="computeroutput"><span class="identifier">Time</span></code>, and <code class="computeroutput"><span class="identifier">d</span></code> |
| denotes a value of type <code class="computeroutput"><span class="identifier">X</span><span class="special">::</span><span class="identifier">duration_type</span></code>. |
| </p> |
| <div class="table"> |
| <a name="id865108"></a><p class="title"><b>Table 35. TimeTraits requirements</b></p> |
| <div class="table-contents"><table class="table" summary="TimeTraits requirements"> |
| <colgroup> |
| <col> |
| <col> |
| <col> |
| </colgroup> |
| <thead><tr> |
| <th> |
| <p> |
| expression |
| </p> |
| </th> |
| <th> |
| <p> |
| return type |
| </p> |
| </th> |
| <th> |
| <p> |
| assertion/note<br> pre/post-condition |
| </p> |
| </th> |
| </tr></thead> |
| <tbody> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">X</span><span class="special">::</span><span class="identifier">time_type</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">Time</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| Represents an absolute time. Must support default construction, |
| and meet the requirements for <code class="computeroutput"><span class="identifier">CopyConstructible</span></code> |
| and <code class="computeroutput"><span class="identifier">Assignable</span></code>. |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">X</span><span class="special">::</span><span class="identifier">duration_type</span></code> |
| </p> |
| </td> |
| <td> |
| </td> |
| <td> |
| <p> |
| Represents the difference between two absolute times. Must support |
| default construction, and meet the requirements for <code class="computeroutput"><span class="identifier">CopyConstructible</span></code> and <code class="computeroutput"><span class="identifier">Assignable</span></code>. A duration can be |
| positive, negative, or zero. |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">X</span><span class="special">::</span><span class="identifier">now</span><span class="special">();</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">time_type</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| Returns the current time. |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">X</span><span class="special">::</span><span class="identifier">add</span><span class="special">(</span><span class="identifier">t</span><span class="special">,</span> |
| <span class="identifier">d</span><span class="special">);</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">time_type</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| Returns a new absolute time resulting from adding the duration |
| <code class="computeroutput"><span class="identifier">d</span></code> to the absolute |
| time <code class="computeroutput"><span class="identifier">t</span></code>. |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">X</span><span class="special">::</span><span class="identifier">subtract</span><span class="special">(</span><span class="identifier">t1</span><span class="special">,</span> |
| <span class="identifier">t2</span><span class="special">);</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">duration_type</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| Returns the duration resulting from subtracting <code class="computeroutput"><span class="identifier">t2</span></code> |
| from <code class="computeroutput"><span class="identifier">t1</span></code>. |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">X</span><span class="special">::</span><span class="identifier">less_than</span><span class="special">(</span><span class="identifier">t1</span><span class="special">,</span> |
| <span class="identifier">t2</span><span class="special">);</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="keyword">bool</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| Returns whether <code class="computeroutput"><span class="identifier">t1</span></code> |
| is to be treated as less than <code class="computeroutput"><span class="identifier">t2</span></code>. |
| </p> |
| </td> |
| </tr> |
| <tr> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">X</span><span class="special">::</span><span class="identifier">to_posix_duration</span><span class="special">(</span><span class="identifier">d</span><span class="special">);</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| <code class="computeroutput"><span class="identifier">date_time</span><span class="special">::</span><span class="identifier">time_duration_type</span></code> |
| </p> |
| </td> |
| <td> |
| <p> |
| Returns the <code class="computeroutput"><span class="identifier">date_time</span><span class="special">::</span><span class="identifier">time_duration_type</span></code> |
| value that most closely represents the duration <code class="computeroutput"><span class="identifier">d</span></code>. |
| </p> |
| </td> |
| </tr> |
| </tbody> |
| </table></div> |
| </div> |
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| <td align="right"><div class="copyright-footer">Copyright © 2003 - 2010 Christopher M. Kohlhoff<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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