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	<title>BOOST_PP_FOR</title>
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	<div style="margin-left:  0px;">
		The <b>BOOST_PP_FOR</b> macro represents a generalized horizontal repetition construct.
	</div>
	<h4>Usage</h4>
		<div class="code">
			<b>BOOST_PP_FOR</b>(<i>state</i>, <i>pred</i>, <i>op</i>, <i>macro</i>)
		</div>
	<h4>Arguments</h4>
		<dl>
			<dt>state</dt>
			<dd>
				The initial state.
			</dd>
			<dt>pred</dt>
			<dd>
				A binary predicate of the form <i>pred</i>(<i>r</i>, <i>state</i>).&nbsp;
				This macro must expand to an integer in the range of <i>0</i> to <b>BOOST_PP_LIMIT_MAG</b>.&nbsp;
				<b>BOOST_PP_FOR</b> repeatedly expands <i>macro</i> while this predicate returns non-zero.&nbsp;
				This macro is called with the next available <b>BOOST_PP_FOR</b> repetition and the current <i>state</i>.
			</dd>
			<dt>op</dt>
			<dd>
				A binary operation of the form <i>op</i>(<i>r</i>, <i>state</i>).&nbsp;
				This operation is expanded by <b>BOOST_PP_FOR</b> with the next available <b>BOOST_PP_FOR</b> repetition and the current <i>state</i>.&nbsp;
				This macro is repeatedly applied to the <i>state</i>, each time producing a new <i>state</i>, until <i>pred</i> returns <i>0</i>.
			</dd>
			<dt>macro</dt>
			<dd>
				A binary macro of the form <i>macro</i>(<i>r</i>, <i>state</i>).&nbsp;
				This macro is expanded by <b>BOOST_PP_FOR</b> with the next available <b>BOOST_PP_FOR</b> repetition and the current <i>state</i>.&nbsp;
				This macro is is repeated by <b>BOOST_PP_FOR</b> until <i>pred</i> returns <i>0</i>.
			</dd>
		</dl>
	<h4>Remarks</h4>
		<div>
			This macro expands to the sequence:
			<div>
				<i>macro</i>(<i>r</i>, <i>state</i>) <i>macro</i>(<i>r</i>, <i>op</i>(<i>r</i>, <i>state</i>)) ... <i>macro</i>(<i>r</i>, <i>op</i>(<i>r</i>, ... <i>op</i>(<i>r</i>, <i>state</i>) ... ))
			</div>
		</div>
		<div>
			The <i>r</i> value that is passed to <i>pred</i>, <i>op</i>, and <i>macro</i> represents the next available <b>BOOST_PP_FOR</b> repetition.&nbsp;
			Other macros that have <b>_R</b> suffix variants internally use <b>BOOST_PP_FOR</b>--for example, <b>BOOST_PP_LIST_FOR_EACH</b> and <b>BOOST_PP_LIST_FOR_EACH_R</b>.&nbsp;
			Using these <b>_R</b> versions is not strictly necessary, but passing the <i>r</i> value (that is passed to <i>pred</i>, <i>op</i>, and <i>macro</i>) to these macros allows them to reenter <b>BOOST_PP_FOR</b> with maximum efficiency.
		</div>
		<div>
			To directly use this <i>r</i> value, rather than simply passing it to another macro, see <b>BOOST_PP_FOR_<i>r</i></b>.
		</div>
		<div>
			Previously, this macro could not be used recursively inside <b>BOOST_PP_FOR</b>.&nbsp;
			This limitation no longer exists, as the library can automatically detect the next available <b>BOOST_PP_FOR</b> repetition.
		</div>
	<h4>See Also</h4>
		<ul>
			<li><a href="for_r.html">BOOST_PP_FOR_<i>r</i></a></li>
			<li><a href="limit_mag.html">BOOST_PP_LIMIT_MAG</a></li>
		</ul>
	<h4>Requirements</h4>
		<div>
			<b>Header:</b> &nbsp;<a href="../headers/repetition/for.html">&lt;boost/preprocessor/repetition/for.hpp&gt;</a>
		</div>
	<h4>Sample Code</h4>
<div><pre>
#include &lt;<a href="../headers/arithmetic/inc.html">boost/preprocessor/arithmetic/inc.hpp</a>&gt;
#include &lt;<a href="../headers/comparison/not_equal.html">boost/preprocessor/comparison/not_equal.hpp</a>&gt;
#include &lt;<a href="../headers/repetition/for.html">boost/preprocessor/repetition/for.hpp</a>&gt;
#include &lt;<a href="../headers/tuple/elem.html">boost/preprocessor/tuple/elem.hpp</a>&gt;

#define PRED(r, state) \
   <a href="not_equal.html">BOOST_PP_NOT_EQUAL</a>( \
      <a href="tuple_elem.html">BOOST_PP_TUPLE_ELEM</a>(2, 0, state), \
      <a href="inc.html">BOOST_PP_INC</a>(<a href="tuple_elem.html">BOOST_PP_TUPLE_ELEM</a>(2, 1, state)) \
   ) \
   /**/

#define OP(r, state) \
   ( \
      <a href="inc.html">BOOST_PP_INC</a>(<a href="tuple_elem.html">BOOST_PP_TUPLE_ELEM</a>(2, 0, state)), \
      <a href="tuple_elem.html">BOOST_PP_TUPLE_ELEM</a>(2, 1, state) \
   ) \
   /**/

#define MACRO(r, state) <a href="tuple_elem.html">BOOST_PP_TUPLE_ELEM</a>(2, 0, state)

<a href="for.html">BOOST_PP_FOR</a>((5, 10), PRED, OP, MACRO) // expands to 5 6 7 8 9 10
</pre></div>
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		<i>© Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i>
		</br><i>© Copyright Paul Mensonides 2002</i>
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	<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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