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1 <html>
2 <head>
3 	<title>BOOST_PP_REPEAT_FROM_TO</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_REPEAT_FROM_TO</b> macro represents a fast horizontal repetition construct.
9 	</div>
10 	<h4>Usage</h4>
11 		<div class="code">
12 			<b>BOOST_PP_REPEAT_FROM_TO</b>(<i>first</i>, <i>last</i>, <i>macro</i>, <i>data</i>)
13 		</div>
14 	<h4>Arguments</h4>
15 		<dl>
16 			<dt>first</dt>
17 			<dd>
18 				The lower bound of the repetition.&nbsp;
19 				Valid values range from <i>0</i> to <b>BOOST_PP_LIMIT_MAG</b>.
20 			</dd>
21 			<dt>last</dt>
22 			<dd>
23 				The upper bound of the repetition.
24 				Valid values range from <i>0</i> to <b>BOOST_PP_LIMIT_MAG</b>.
25 			</dd>
26 			<dt>macro</dt>
27 			<dd>
28 				A ternary operation of the form <i>macro</i>(<i>z</i>, <i>n</i>, <i>data</i>).&nbsp;
29 				This macro is expanded by <b>BOOST_PP_REPEAT</b> with the next available repetition depth,
30 				the current repetition number, and the auxiliary <i>data</i> argument.&nbsp;
31 			</dd>
32 			<dt>data</dt>
33 			<dd>
34 				Auxiliary data passed to <i>macro</i>.
35 			</dd>
36 		</dl>
37 	<h4>Remarks</h4>
38 		<div>
39 			This macro expands to the sequence:
40 			<div>
41 				<i>macro</i>(<i>z</i>, <i>first</i>, <i>data</i>) <i>macro</i>(<i>z</i>, <i>first</i> + <i>1</i>, <i>data</i>) ... <i>macro</i>(<i>z</i>, <i>last</i> - <i>1</i>, <i>data</i>)
42 			</div>
43 		</div>
44 		<div>
45 			The number of repetitions (i.e. <i>last</i> - <i>first</i>) must not exceed <b>BOOST_PP_LIMIT_REPEAT</b>.
46 		</div>
47 		<div>
48 			The <i>z</i> value that is passed to <i>macro</i> represents the next available repetition dimension.&nbsp;
49 			Other macros that have <b>_Z</b> suffix variants internally use <b>BOOST_PP_REPEAT</b>--for example, <b>BOOST_PP_ENUM_PARAMS</b> and <b>BOOST_PP_ENUM_PARAMS_Z</b>.&nbsp;
50 			Using these <b>_Z</b> versions is not strictly necessary, but passing the <i>z</i> value (that is passed to <i>macro</i>) to these macros allows them to reenter <b>BOOST_PP_REPEAT</b> with maximum efficiency.
51 		</div>
52 		<div>
53 			To directly use this <i>z</i> value, rather than simply passing it to another macro, see <b>BOOST_PP_REPEAT_FROM_TO_<i>z</i></b>.
54 		</div>
55 		<div>
56 			Previously, this macro could not be used recursively inside <b>BOOST_PP_REPEAT</b>.&nbsp;
57 			This limitation no longer exists, as the library can automatically detect the next available repetition depth.
58 		</div>
59 		<div>
60 			This macro also uses <b>BOOST_PP_WHILE</b>.&nbsp;
61 			Because of this, there are also two variants of this macro for ideal reentrance into <b>BOOST_PP_WHILE</b>,
62 			<b>BOOST_PP_REPEAT_FROM_TO_D</b> and <b>BOOST_PP_REPEAT_FROM_TO_D_<i>z</i>.
63 		</div>
64 	<h4>See Also</h4>
65 		<ul>
66 			<li><a href="limit_mag.html">BOOST_PP_LIMIT_MAG</a></li>
67 			<li><a href="limit_repeat.html">BOOST_PP_LIMIT_REPEAT</a></li>
68 			<li><a href="repeat_from_to_d.html">BOOST_PP_REPEAT_FROM_TO_D</a></li>
69 			<li><a href="repeat_from_to_d_z.html">BOOST_PP_REPEAT_FROM_TO_D_<i>z</i></a></li>
70 			<li><a href="repeat_from_to_z.html">BOOST_PP_REPEAT_FROM_TO_<i>z</i></a></li>
71 		</ul>
72 	<h4>Requirements</h4>
73 		<div>
74 			<b>Header:</b> &nbsp;<a href="../headers/repetition/repeat_from_to.html">&lt;boost/preprocessor/repetition/repeat_from_to.hpp&gt;</a>
75 		</div>
76 	<h4>Sample Code</h4>
77 <div><pre>
78 #include &lt;<a href="../headers/cat.html">boost/preprocessor/cat.hpp</a>&gt;
79 #include &lt;<a href="../headers/repetition/repeat_from_to.html">boost/preprocessor/repetition/repeat_from_to.hpp</a>&gt;
80 
81 #define DECL(z, n, text) <a href="cat.html">BOOST_PP_CAT</a>(text, n) = n;
82 
83 <a href="repeat_from_to.html">BOOST_PP_REPEAT_FROM_TO</a>(5, 10, DECL, int x)
84    /*
85       expands to:
86       int x5 = 5; int x6 = 6; int x7 = 7;
87       int x8 = 8; int x9 = 9;
88    */
89 </pre></div>
90 	<hr size="1">
91 	<div style="margin-left: 0px;">
92 		<i>� Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i>
93 		</br><i>� Copyright Paul Mensonides 2002</i>
94 	</div>
95 	<div style="margin-left: 0px;">
96 		<p><small>Distributed under the Boost Software License, Version 1.0. (See
97 		accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or
98 		copy at <a href=
99 		"http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</small></p>
100 	</div>
101 </body>
102 </html>
103