ceph/src/boost/libs/locale/doc/html/faq.html

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  69 <li><a class="anchor" id="faq_bad_cast"></a><b>I try to use some Boost.Locale functions and I get an <code>std::bad_cast</code> exception thrown?</b> <br/>
  70  <br/>
  71  <b>Answer:</b> You probably try to use incorrect <code>std::locale</code> object. All Boost.Locale tools relay on <code>std::locale</code> object's facets. The locale object should be generated with <a class="el" href="classboost_1_1locale_1_1generator.html">generator</a> class and then passed to the function or alternatively global locale should be set using <code>std::locale::global()</code> function such that global locale (and default created one) would have required facets to use.</li>
  72 <li><a class="anchor" id="faq_number"></a><b>I had installed global locale and try to write something to stream but still get wrong output?</b> For example: <div class="fragment"><div class="line"><span class="preprocessor">#include &lt;boost/locale.hpp&gt;</span></div>
  73 <div class="line"><span class="preprocessor">#include &lt;iostream&gt;</span></div>
  74 <div class="line"><span class="keywordtype">int</span> main()</div>
  75 <div class="line">{</div>
  76 <div class="line">    <a class="code" href="classboost_1_1locale_1_1generator.html">boost::locale::generator</a> gen;</div>
  77 <div class="line">    std::locale::global(gen(<span class="stringliteral">&quot;&quot;</span>));</div>
  78 <div class="line">    std::cout &lt;&lt; <a class="code" href="group__manipulators.html#gae05b82e6658dc573521518fed5f5c77f">boost::locale::as::date</a> &lt;&lt; <a class="code" href="group__manipulators.html#gae669b101cbeaed6f6d246ebdcaa8f39c">std::time</a>(0) &lt;&lt; std::endl;</div>
  79 <div class="line">}</div>
  80 </div><!-- fragment --> Prints a number instead of a date. <br/>
  81  <b>Answer:</b> You forget to imbue the locale to the stream. Changing the global locale does not affect the locale in existing <code>iostream</code> objects. Thus because <code>std::out</code> and other global streams were created before changing the global locale Boost.Locale manipulators have no effect. You need to write: <div class="fragment"><div class="line"><span class="preprocessor">#include &lt;boost/locale.hpp&gt;</span></div>
  82 <div class="line"><span class="preprocessor">#include &lt;iostream&gt;</span></div>
  83 <div class="line"><span class="keywordtype">int</span> main()</div>
  84 <div class="line">{</div>
  85 <div class="line">    <a class="code" href="classboost_1_1locale_1_1generator.html">boost::locale::generator</a> gen;</div>
  86 <div class="line">    std::locale l = gen(<span class="stringliteral">&quot;&quot;</span>);</div>
  87 <div class="line">    std::locale::global(l);</div>
  88 <div class="line">    std::cout.imbue(l);</div>
  89 <div class="line">    std::cout &lt;&lt; <a class="code" href="group__manipulators.html#gae05b82e6658dc573521518fed5f5c77f">boost::locale::as::date</a> &lt;&lt; <a class="code" href="group__manipulators.html#gae669b101cbeaed6f6d246ebdcaa8f39c">std::time</a>(0) &lt;&lt; std::endl;</div>
  90 <div class="line">}</div>
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