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1<html>
2<head>
3	<title>BOOST_PP_ITERATE</title>
4	<link rel="stylesheet" type="text/css" href="../styles.css">
5</head>
6<body>
7	<div style="margin-left:  0px;">
8		The <b>BOOST_PP_ITERATE</b> macro initiates a <i>file-iteration</i>.
9	</div>
10	<h4>Usage</h4>
11		<div class="code">
12			#include <b>BOOST_PP_ITERATE</b>()
13		</div>
14	<h4>Remarks</h4>
15		<div>
16			Arguments to this macro are passed as <i>external named arguments</i> in one of two
17			ways--either through <b>BOOST_PP_FILENAME_<i>x</i></b> and <b>BOOST_PP_ITERATION_LIMITS</b> <i>or</i>
18			through <b>BOOST_PP_ITERATION_PARAMS_<i>x</i></b>.&nbsp;
19		</div>
20		<div>
21			Three pieces of information are required to perform a <i>file-iteration</i>.&nbsp;
22			First, the name of a file to iterate over.&nbsp;
23			This is passed via <b>BOOST_PP_FILENAME_<i>x</i></b> <i>or</i> as part of <b>BOOST_PP_ITERATION_PARAMS_<i>x</i></b>.&nbsp;
24			The <i>file-iteration</i> mechanism will repeatedly include this file with iteration values ranging from a lower bound to an upper bound--the second and third <i>required</i> parameters.&nbsp;
25			These two boundaries are either passed through <b>BOOST_PP_ITERATION_LIMITS</b> <i>or</i> as part of <b>BOOST_PP_ITERATION_PARAMS_<i>x</i></b>.
26		</div>
27		<div>
28			Optionally, a fourth parameter may be passed that associates flags with an iteration.&nbsp;
29			These flags are primarily useful to distinguish one iteration from another in the same file.&nbsp;
30			This parameter can only be passed through <b>BOOST_PP_ITERATION_PARAMS_<i>x</i></b>.
31		</div>
32		<div>
33			While a <i>file-iteration</i> is in progress, <b>BOOST_PP_IS_ITERATING</b> is defined as <i>1</i>.
34		</div>
35	<h4>See Also</h4>
36		<ul>
37			<li><a href="filename_x.html">BOOST_PP_FILENAME_<i>x</i></a></li>
38			<li><a href="is_iterating.html">BOOST_PP_IS_ITERATING</a></li>
39			<li><a href="iteration_limits.html">BOOST_PP_ITERATION_LIMITS</a></li>
40			<li><a href="iteration_params_x.html">BOOST_PP_ITERATION_PARAMS_<i>x</i></a></li>
41		</ul>
42	<h4>Requirements</h4>
43		<div>
44			<b>Header:</b> &nbsp;<a href="../headers/iteration/iterate.html">&lt;boost/preprocessor/iteration/iterate.hpp&gt;</a>
45		</div>
46	<h4>Sample Code</h4>
47<div><pre>
48// file.h
49#if !<a href="is_iterating.html">BOOST_PP_IS_ITERATING</a>
50
51   #ifndef FILE_H_
52   #define FILE_H_
53
54   #include &lt;<a href="../headers/iteration/iterate.html">boost/preprocessor/iteration/iterate.hpp</a>&gt;
55
56   #define <a href="iteration_params_x.html">BOOST_PP_ITERATION_PARAMS_1</a> (3, (1, 10, "file.h"))
57   #include <a href="iterate.html">BOOST_PP_ITERATE</a>()
58
59   #define <a href="filename_x.html">BOOST_PP_FILENAME_1</a> "file.h"
60   #define <a href="iteration_limits.html">BOOST_PP_ITERATION_LIMITS</a> (11, 20)
61   #include <a href="iterate.html">BOOST_PP_ITERATE</a>()
62
63   #endif
64
65#else
66
67   current iteration value is <a href="iteration.html">BOOST_PP_ITERATION</a>()
68
69#endif
70</pre></div>
71	<hr size="1">
72	<div style="margin-left: 0px;">
73		<i>� Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i>
74		</br><i>� Copyright Paul Mensonides 2002</i>
75	</div>
76	<div style="margin-left: 0px;">
77		<p><small>Distributed under the Boost Software License, Version 1.0. (See
78		accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or
79		copy at <a href=
80		"http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</small></p>
81	</div>
82</body>
83</html>
84