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1<html>
2<head>
3	<title>BOOST_PP_MUL_D</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_MUL_D</b> macro expands to the product of its second and third arguments.&nbsp;
9		It reenters <b>BOOST_PP_WHILE</b> with maximum efficiency.
10	</div>
11	<h4>Usage</h4>
12		<div class="code">
13			<b>BOOST_PP_MUL_D</b>(<i>d</i>, <i>x</i>, <i>y</i>)
14		</div>
15	<h4>Arguments</h4>
16		<dl>
17			<dt>d</dt>
18			<dd>
19				The next available <b>BOOST_PP_WHILE</b> iteration.&nbsp;
20			</dd>
21			<dt>x</dt>
22			<dd>
23				The multiplicand of the operation.&nbsp;
24				Valid values range from <i>0</i> to <b>BOOST_PP_LIMIT_MAG</b>.
25			</dd>
26			<dt>y</dt>
27			<dd>
28				The multiplier of the operation.&nbsp;
29				Valid values range from <i>0</i> to <b>BOOST_PP_LIMIT_MAG</b>.
30			</dd>
31		</dl>
32	<h4>Remarks</h4>
33		<div>
34			If the product of <i>x</i> and <i>y</i> is greater than <b>BOOST_PP_LIMIT_MAG</b>, the result is saturated to <b>BOOST_PP_LIMIT_MAG</b>.
35		</div>
36		<div>
37			This macro is the most efficient when <i>x</i> is greater than or equal to <i>y</i>.&nbsp;
38			However, the efficiency gain is not worth actually comparing the two arguments prior to invocation.&nbsp;
39			In other words, <i>x</i> should be the value that is <i>most likely</i> to be the largest of the two operands.
40		</div>
41	<h4>See Also</h4>
42		<ul>
43			<li><a href="limit_mag.html">BOOST_PP_LIMIT_MAG</a></li>
44			<li><a href="mul.html">BOOST_PP_MUL</a></li>
45		</ul>
46	<h4>Requirements</h4>
47		<div>
48			<b>Header:</b> &nbsp;<a href="../headers/arithmetic/mul.html">&lt;boost/preprocessor/arithmetic/mul.hpp&gt;</a>
49		</div>
50	<h4>Sample Code</h4>
51<div><pre>
52#include &lt;<a href="../headers/arithmetic/dec.html">boost/preprocessor/arithmetic/dec.hpp</a>&gt;
53#include &lt;<a href="../headers/arithmetic/mul.html">boost/preprocessor/arithmetic/mul.hpp</a>&gt;
54#include &lt;<a href="../headers/control/while.html">boost/preprocessor/control/while.hpp</a>&gt;
55#include &lt;<a href="../headers/tuple/elem.html">boost/preprocessor/tuple/elem.hpp</a>&gt;
56
57#define PRED(d, data) <a href="tuple_elem.html">BOOST_PP_TUPLE_ELEM</a>(3, 0, data)
58
59#define OP(d, data) \
60   ( \
61      <a href="dec.html">BOOST_PP_DEC</a>( \
62         <a href="tuple_elem.html">BOOST_PP_TUPLE_ELEM</a>(3, 0, data) \
63      ), \
64      <a href="tuple_elem.html">BOOST_PP_TUPLE_ELEM</a>(3, 1, data), \
65      <a href="mul_d.html">BOOST_PP_MUL_D</a>( \
66         d, \
67         <a href="tuple_elem.html">BOOST_PP_TUPLE_ELEM</a>(3, 2, data), \
68         <a href="tuple_elem.html">BOOST_PP_TUPLE_ELEM</a>(3, 1, data) \
69      ) \
70   ) \
71   /**/
72
73// raise 'x' to the 'n'-th power
74#define EXP(x, n) <a href="tuple_elem.html">BOOST_PP_TUPLE_ELEM</a>(3, 2, <a href="while.html">BOOST_PP_WHILE</a>(PRED, OP, (n, x, 1)))
75
76EXP(4, 2) // expands to 16
77EXP(2, 3) // expands to 8
78</pre></div>
79	<hr size="1">
80	<div style="margin-left: 0px;">
81		<i>� Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i>
82		</br><i>� Copyright Paul Mensonides 2002</i>
83	</div>
84	<div style="margin-left: 0px;">
85		<p><small>Distributed under the Boost Software License, Version 1.0. (See
86		accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or
87		copy at <a href=
88		"http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</small></p>
89	</div>
90</body>
91</html>
92