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. 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. 20 </dd> 21 <dt>x</dt> 22 <dd> 23 The multiplicand of the operation. 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. 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>. 38 However, the efficiency gain is not worth actually comparing the two arguments prior to invocation. 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> <a href="../headers/arithmetic/mul.html"><boost/preprocessor/arithmetic/mul.hpp></a> 49 </div> 50 <h4>Sample Code</h4> 51 <div><pre> 52 #include <<a href="../headers/arithmetic/dec.html">boost/preprocessor/arithmetic/dec.hpp</a>> 53 #include <<a href="../headers/arithmetic/mul.html">boost/preprocessor/arithmetic/mul.hpp</a>> 54 #include <<a href="../headers/control/while.html">boost/preprocessor/control/while.hpp</a>> 55 #include <<a href="../headers/tuple/elem.html">boost/preprocessor/tuple/elem.hpp</a>> 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 76 EXP(4, 2) // expands to 16 77 EXP(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