/doxy.html#header.boost.date_time.posix_time.date_duration_operators_hpp" title="Header &lt;boost/date_time/posix_time/date_duration_operators.hpp&gt;">boost/date_time/posix_time/date_duration_operators.hpp</a>&gt;

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<a class="link" href="ptime.html" title="Class ptime">ptime</a> <span class="keyword">operator</span><span class="special">-=</span><span class="special">(</span><a class="link" href="ptime.html" title="Class ptime">ptime</a> <span class="special">&amp;</span> t<span class="special">,</s