1<html> 2<head> 3 <title>BOOST_PP_ENUM_z</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_ENUM_<i>z</i></b> macro represents a reentry into the <b>BOOST_PP_ENUM</b> repetition construct. 9 </div> 10 <h4>Usage</h4> 11 <div class="code"> 12 <b>BOOST_PP_ENUM_</b> ## <i>z</i>(<i>count</i>, <i>macro</i>, <i>data</i>) 13 </div> 14 <h4>Arguments</h4> 15 <dl> 16 <dt>z</dt> 17 <dd> 18 The next available <b>BOOST_PP_REPEAT</b> dimension. 19 </dd> 20 <dt>count</dt> 21 <dd> 22 The number of repetitious calls to <i>macro</i>. 23 Valid values range from <i>0</i> to <b>BOOST_PP_LIMIT_REPEAT</b>. 24 </dd> 25 <dt>macro</dt> 26 <dd> 27 A ternary operation of the form <i>macro</i>(<i>z</i>, <i>n</i>, <i>data</i>). 28 This macro is expanded by <b>BOOST_PP_ENUM</b> with the next available repetition depth, 29 the current repetition number, and the auxiliary <i>data</i> argument. 30 </dd> 31 <dt>data</dt> 32 <dd> 33 Auxiliary data passed to <i>macro</i>. 34 </dd> 35 </dl> 36 <h4>Remarks</h4> 37 <div> 38 This macro expands to the sequence: 39 <div> 40 <i>macro</i>(<i>z</i>, <i>0</i>, <i>data</i>), <i>macro</i>(<i>z</i>, <i>1</i>, <i>data</i>), ... <i>macro</i>(<i>z</i>, <i>count</i> - <i>1</i>, <i>data</i>) 41 </div> 42 </div> 43 <div> 44 At certain times, it may be necessary to perform the concatenation with <b>BOOST_PP_CAT</b> rather than the preprocessor token-pasting operator. 45 This happens when the <i>z</i> value is a macro invocation itself. 46 It needs a delay to allow it to expand. 47 The syntax in such a scenario becomes: 48 <div> 49 <b>BOOST_PP_CAT</b>(<b>BOOST_PP_ENUM_</b>, <i>z</i>)(<i>count</i>, <i>macro</i>, <i>data</i>) 50 </div> 51 </div> 52 <h4>See Also</h4> 53 <ul> 54 <li><a href="cat.html">BOOST_PP_CAT</a></li> 55 <li><a href="enum.html">BOOST_PP_ENUM</a></li> 56 <li><a href="limit_repeat.html">BOOST_PP_LIMIT_REPEAT</a></li> 57 </ul> 58 <h4>Requirements</h4> 59 <div> 60 <b>Header:</b> <a href="../headers/repetition/enum.html"><boost/preprocessor/repetition/enum.hpp></a> 61 </div> 62 <h4>Sample Code</h4> 63<div><pre> 64#include <<a href="../headers/arithmetic/inc.html">boost/preprocessor/arithmetic/inc.hpp</a>> 65#include <<a href="../headers/repetition/enum.html">boost/preprocessor/repetition/enum.hpp</a>> 66 67#define TEXT(z, n, text) text 68 69#define TTP(z, n, _) \ 70 template< \ 71 <a href="enum_z.html">BOOST_PP_ENUM_</a> ## z(<a href="inc.html">BOOST_PP_INC</a>(n), TEXT, class) \ 72 > \ 73 class T ## n \ 74 /**/ 75 76<a href="enum.html">BOOST_PP_ENUM</a>(3, TTP, nil) 77 /* 78 expands to... 79 template<class> class T0, 80 template<class, class> class T1, 81 template<class, class, class> class T2 82 */ 83</pre></div> 84 <hr size="1"> 85 <div style="margin-left: 0px;"> 86 <i>� Copyright <a href="http://www.housemarque.com" target="_top">Housemarque Oy</a> 2002</i> 87 </br><i>� Copyright Paul Mensonides 2002</i> 88 </div> 89 <div style="margin-left: 0px;"> 90 <p><small>Distributed under the Boost Software License, Version 1.0. (See 91 accompanying file <a href="../../../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or 92 copy at <a href= 93 "http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a>)</small></p> 94 </div> 95</body> 96</html> 97