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  4. <title>BOOST_PP_LIST_TO_TUPLE</title>
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  8. <div style="margin-left: 0px;"> The <b>BOOST_PP_LIST_TO_TUPLE</b> macro
  9. converts a <i>list</i> to a <i>tuple</i>. </div>
  10. <h4>Usage</h4>
  11. <div class="code"> <b>BOOST_PP_LIST_TO_TUPLE</b>(<i>list</i>) </div>
  12. <h4>Arguments</h4>
  13. <dl>
  14. <dt>list</dt>
  15. <dd> The <i>list</i> to be converted. </dd>
  16. </dl>
  17. <h4>Remarks</h4>
  18. <div> If <i>list</i> is, for example, (<i>a</i>, (<i>b</i>, (<i>c</i>, <b>BOOST_PP_NIL</b>))),
  19. this macro will produce:
  20. <div> (<i>a</i>, <i>b</i>, <i>c</i>) </div>
  21. </div>
  22. <div> Previously, this macro could not be used inside <b>BOOST_PP_FOR</b>.&nbsp;
  23. There is no longer any such restriction.&nbsp; It is more efficient,
  24. however, to use <b>BOOST_PP_LIST_TO_TUPLE_R</b> in such a situation.<br>
  25. <br>
  26. If the <i>list</i> to be converted is empty, as represented by 'BOOST_PP_NIL',
  27. the resulting <i>tuple</i> is undefined since a <i>tuple</i> cannot be
  28. empty.</div>
  29. <h4>See Also</h4>
  30. <ul>
  31. <li><a href="list_to_tuple_r.html">BOOST_PP_LIST_TO_TUPLE_R</a></li>
  32. </ul>
  33. <h4>Requirements</h4>
  34. <div> <b>Header:</b> &nbsp;<a href="../headers/list/to_tuple.html">&lt;boost/preprocessor/list/to_tuple.hpp&gt;</a>
  35. </div>
  36. <h4>Sample Code</h4>
  37. <div>
  38. <pre>#include &lt;<a href="../headers/list/to_tuple.html">boost/preprocessor/list/to_tuple.hpp</a>&gt;
  39. #define LIST (w, (x, (y, (z, <a href="nil.html">BOOST_PP_NIL</a>))))
  40. <a href="list_to_tuple.html">BOOST_PP_LIST_TO_TUPLE</a>(LIST) // expands to (w, x, y, z)
  41. </pre></div>
  42. <hr size="1">
  43. <div style="margin-left: 0px;"> <i>© Copyright <a href="http://www.housemarque.com"
  44. target="_top">Housemarque Oy</a> 2002</i> <br>
  45. <i>© Copyright Paul Mensonides 2002</i> </div>
  46. <div style="margin-left: 0px;">
  47. <p><small>Distributed under the Boost Software License, Version 1.0. (See
  48. accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a>
  49. or copy at <a href="http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</small></p>
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