mirror of
https://github.com/boostorg/preprocessor.git
synced 2025-06-30 22:40:58 +02:00
73 lines
2.6 KiB
HTML
73 lines
2.6 KiB
HTML
<html>
|
|
<head>
|
|
<title>BOOST_PP_ENUM_TRAILING</title>
|
|
<link rel="stylesheet" type="text/css" href="../styles.css">
|
|
</head>
|
|
<body>
|
|
<div style="margin-left: 0px;">
|
|
The <b>BOOST_PP_ENUM_TRAILING</b> macro generates a comma-separated list with a leading comma.
|
|
</div>
|
|
<h4>Usage</h4>
|
|
<div class="code">
|
|
<b>BOOST_PP_ENUM_TRAILING</b>(<i>count</i>, <i>macro</i>, <i>data</i>)
|
|
</div>
|
|
<h4>Arguments</h4>
|
|
<dl>
|
|
<dt>count</dt>
|
|
<dd>
|
|
The number of repetitious calls to <i>macro</i>.
|
|
Valid values range from <i>0</i> to <b>BOOST_PP_LIMIT_REPEAT</b>.
|
|
</dd>
|
|
<dt>macro</dt>
|
|
<dd>
|
|
A ternary operation of the form <i>macro</i>(<i>z</i>, <i>n</i>, <i>data</i>).
|
|
This macro is expanded by <b>BOOST_PP_ENUM</b> with the next available repetition depth,
|
|
the current repetition number, and the auxiliary <i>data</i> argument.
|
|
</dd>
|
|
<dt>data</dt>
|
|
<dd>
|
|
Auxiliary data passed to <i>macro</i>.
|
|
</dd>
|
|
</dl>
|
|
<h4>Remarks</h4>
|
|
<div>
|
|
This macro expands to the comma-separated sequence:
|
|
<div>
|
|
, <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>)
|
|
</div>
|
|
</div>
|
|
<div>
|
|
The <i>z</i> value that is passed to <i>macro</i> represents the next available repetition dimension.
|
|
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>.
|
|
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.
|
|
</div>
|
|
<div>
|
|
To directly use this <i>z</i> value, rather than simply passing it to another macro, see <b>BOOST_PP_ENUM_TRAILING_<i>z</i></b>.
|
|
</div>
|
|
<h4>See Also</h4>
|
|
<ul>
|
|
<li><a href="enum_trailing_z.html">BOOST_PP_ENUM_TRAILING_<i>z</i></a></li>
|
|
<li><a href="limit_repeat.html">BOOST_PP_LIMIT_REPEAT</a></li>
|
|
</ul>
|
|
<h4>Requirements</h4>
|
|
<div>
|
|
<b>Header:</b> <a href="../headers/repetition/enum_trailing.hpp.html"><boost/preprocessor/repetition/enum_trailing.hpp></a>
|
|
</div>
|
|
<h4>Sample Code</h4>
|
|
<div><pre>
|
|
#include <<a href="../headers/repetition/enum_trailing.hpp.html">boost/preprocessor/repetition/enum_trailing.hpp</a>>
|
|
|
|
#define TEXT(z, n, text) text
|
|
|
|
template<class <a href="enum_trailing.html">BOOST_PP_ENUM_TRAILING</a>(3, TEXT, class)>
|
|
class X { };
|
|
/*
|
|
expands to...
|
|
|
|
template<class, class, class, class>
|
|
class X { };
|
|
*/
|
|
</pre></div>
|
|
</body>
|
|
</html>
|