title: How to convert tuple to byte array in c++11
body: <p>I need to write a function to convert tuple to byte array.
  The type of tuple may include <code>int, long, double, std::string, char*</code>,etc.
  The size and type of tuple are arbitrary, such as</p>
  
  <pre><code>std:tuple&lt;string, int, double&gt; t1("abc", 1, 1.3);
  </code></pre>
  
  <p>or</p>
  
  <pre><code>std:tuple&lt;char*, int, int, float, double, string&gt; t2("abc", 1, 2, 1.3, 1.4, "hello");
  </code></pre>
  
  <p>I want use these tuple as input, and the byte array as return value. What should I do ? </p>