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| <title>BOOST_PP_LIST_FOR_EACH_I</title> |
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| The <b>BOOST_PP_LIST_FOR_EACH_I</b> macro repeats a macro for each element in a <i>list</i>. |
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| <h4>Usage</h4> |
| <div class="code"> |
| <b>BOOST_PP_LIST_FOR_EACH_I</b>(<i>macro</i>, <i>data</i>, <i>list</i>) |
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| <h4>Arguments</h4> |
| <dl> |
| <dt>macro</dt> |
| <dd> |
| A macro of the form <i>macro</i>(<i>r</i>, <i>data</i>, <i>i</i>, <i>elem</i>). |
| This macro is expanded by <b>BOOST_PP_LIST_FOR_EACH_I</b> with each element in <i>list</i>. |
| It is expanded with the next available <b>BOOST_PP_FOR</b> repetition, the auxiliary <i>data</i>, the index of the current element, and the current element. |
| </dd> |
| <dt>data</dt> |
| <dd> |
| Auxiliary data passed to <i>macro</i>. |
| </dd> |
| <dt>list</dt> |
| <dd> |
| The <i>list</i> for which <i>macro</i> will be invoked on each element. |
| </dd> |
| </dl> |
| <h4>Remarks</h4> |
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| This macro is a repetition construct. |
| If <i>list</i> is (<i>a</i>, (<i>b</i>, (<i>c</i>, <b>BOOST_PP_NIL</b>))), it expands to the sequence: |
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| <i>macro</i>(<i>r</i>, <i>data</i>, <i>0</i>, <i>a</i>) <i>macro</i>(<i>r</i>, <i>data</i>, <i>1</i>, <i>b</i>) <i>macro</i>(<i>r</i>, <i>data</i>, <i>2</i>, <i>c</i>) |
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| Previously, this macro could not be used inside <b>BOOST_PP_FOR</b>. |
| There is no longer any such restriction. |
| It is more efficient, however, to use <b>BOOST_PP_LIST_FOR_EACH_I_R</b> in such a situation. |
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| <h4>See Also</h4> |
| <ul> |
| <li><a href="list_for_each_i_r.html">BOOST_PP_LIST_FOR_EACH_I_R</a></li> |
| </ul> |
| <h4>Requirements</h4> |
| <div> |
| <b>Header:</b> <a href="../headers/list/for_each_i.html"><boost/preprocessor/list/for_each_i.hpp></a> |
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| <h4>Sample Code</h4> |
| <div><pre> |
| #include <<a href="../headers/cat.html">boost/preprocessor/cat.hpp</a>> |
| #include <<a href="../headers/list/for_each_i.html">boost/preprocessor/list/for_each_i.hpp</a>> |
| |
| #define LIST (w, (x, (y, (z, <a href="nil.html">BOOST_PP_NIL</a>)))) |
| |
| #define MACRO(r, data, i, elem) <a href="cat.html">BOOST_PP_CAT</a>(elem, <a href="cat.html">BOOST_PP_CAT</a>(data, i)) |
| |
| <a href="list_for_each_i.html">BOOST_PP_LIST_FOR_EACH_I</a>(MACRO, _, LIST) // expands to w_0 x_1 y_2 z_3 |
| </pre></div> |
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| <div style="margin-left: 0px;"> |
| <i>© Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i> |
| </br><i>© Copyright Paul Mensonides 2002</i> |
| </div> |
| <div style="margin-left: 0px;"> |
| <p><small>Distributed under the Boost Software License, Version 1.0. (See |
| accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> 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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