1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 2<html> 3<head> 4<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 5<title>Class template wrapping_int</title> 6<link rel="stylesheet" href="../../../../doc/src/boostbook.css" type="text/css"> 7<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 8<link rel="home" href="../../index.html" title="The Boost C++ Libraries BoostBook Documentation Subset"> 9<link rel="up" href="../../date_time/doxy.html#header.boost.date_time.wrapping_int_hpp" title="Header <boost/date_time/wrapping_int.hpp>"> 10<link rel="prev" href="tz_db_base.html" title="Class template tz_db_base"> 11<link rel="next" href="wrapping_int2.html" title="Class template wrapping_int2"> 12</head> 13<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 14<table cellpadding="2" width="100%"><tr> 15<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" 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name="boost.date_time.wrapping_int"></a><div class="titlepage"></div> 28<div class="refnamediv"> 29<h2><span class="refentrytitle">Class template wrapping_int</span></h2> 30<p>boost::date_time::wrapping_int — A wrapping integer used to support time durations (WARNING: only instantiate with a signed type) </p> 31</div> 32<h2 xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv-title">Synopsis</h2> 33<div xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="refsynopsisdiv"><pre class="synopsis"><span class="comment">// In header: <<a class="link" href="../../date_time/doxy.html#header.boost.date_time.wrapping_int_hpp" title="Header <boost/date_time/wrapping_int.hpp>">boost/date_time/wrapping_int.hpp</a>> 34 35</span><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> int_type_<span class="special">,</span> <span class="identifier">int_type_</span> wrap_val<span class="special">></span> 36<span class="keyword">class</span> <a class="link" href="wrapping_int.html" title="Class template wrapping_int">wrapping_int</a> <span class="special">{</span> 37<span class="keyword">public</span><span class="special">:</span> 38 <span class="comment">// types</span> 39 <span class="keyword">typedef</span> <span class="identifier">int_type_</span> <a name="boost.date_time.wrapping_int.int_type"></a><span class="identifier">int_type</span><span class="special">;</span> 40 41 <span class="comment">// <a class="link" href="wrapping_int.html#boost.date_time.wrapping_intconstruct-copy-destruct">construct/copy/destruct</a></span> 42 <a class="link" href="wrapping_int.html#id-1_3_14_15_3_59_1_1_1_7-bb"><span class="identifier">wrapping_int</span></a><span class="special">(</span><span class="identifier">int_type</span><span class="special">)</span><span class="special">;</span> 43 44 <span class="comment">// <a class="link" href="wrapping_int.html#id-1_3_14_15_3_59_1_1_1_5-bb">public static functions</a></span> 45 <span class="keyword">static</span> <span class="identifier">BOOST_CONSTEXPR</span> <span class="identifier">int_type</span> <a class="link" href="wrapping_int.html#id-1_3_14_15_3_59_1_1_1_5_1-bb"><span class="identifier">wrap_value</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span> 46 47 <span class="comment">// <a class="link" href="wrapping_int.html#id-1_3_14_15_3_59_1_1_1_6-bb">public member functions</a></span> 48 <span class="identifier">BOOST_CONSTEXPR</span> <span class="identifier">int_type</span> <a class="link" href="wrapping_int.html#id-1_3_14_15_3_59_1_1_1_6_1-bb"><span class="identifier">as_int</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 49 <span class="identifier">BOOST_CONSTEXPR</span> <a class="link" href="wrapping_int.html#id-1_3_14_15_3_59_1_1_1_6_2-bb"><span class="keyword">operator</span> <span class="identifier">int_type</span></a><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span> 50 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> IntT<span class="special">></span> <span class="identifier">BOOST_CXX14_CONSTEXPR</span> <span class="identifier">IntT</span> <a class="link" href="wrapping_int.html#id-1_3_14_15_3_59_1_1_1_6_3-bb"><span class="identifier">add</span></a><span class="special">(</span><span class="identifier">IntT</span><span class="special">)</span><span class="special">;</span> 51 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> IntT<span class="special">></span> <span class="identifier">BOOST_CXX14_CONSTEXPR</span> <span class="identifier">IntT</span> <a class="link" href="wrapping_int.html#id-1_3_14_15_3_59_1_1_1_6_4-bb"><span class="identifier">subtract</span></a><span class="special">(</span><span class="identifier">IntT</span><span class="special">)</span><span class="special">;</span> 52 53 <span class="comment">// <a class="link" href="wrapping_int.html#id-1_3_14_15_3_59_1_1_1_8-bb">private member functions</a></span> 54 <span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> IntT<span class="special">></span> <span class="identifier">BOOST_CXX14_CONSTEXPR</span> <span class="identifier">IntT</span> <a class="link" href="wrapping_int.html#id-1_3_14_15_3_59_1_1_1_8_1-bb"><span class="identifier">calculate_wrap</span></a><span class="special">(</span><span class="identifier">IntT</span><span class="special">)</span><span class="special">;</span> 55<span class="special">}</span><span class="special">;</span></pre></div> 56<div class="refsect1"> 57<a name="id-1.3.14.15.3.58.3.4"></a><h2>Description</h2> 58<p>In composite date and time types this type is used to wrap at the day boundary. Ex: A wrapping_int<short, 10> will roll over after nine, and roll under below zero. This gives a range of [0,9]</p> 59<p>NOTE: it is strongly recommended that <a class="link" href="wrapping_int2.html" title="Class template wrapping_int2">wrapping_int2</a> be used instead of <a class="link" href="wrapping_int.html" title="Class template wrapping_int">wrapping_int</a> as <a class="link" href="wrapping_int.html" title="Class template wrapping_int">wrapping_int</a> is to be depricated at some point soon.</p> 60<p>Also Note that warnings will occur if instantiated with an unsigned type. Only a signed type should be used! </p> 61<div class="refsect2"> 62<a name="id-1.3.14.15.3.58.3.4.5"></a><h3> 63<a name="boost.date_time.wrapping_intconstruct-copy-destruct"></a><code class="computeroutput">wrapping_int</code> 64 public 65 construct/copy/destruct</h3> 66<div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"> 67<pre class="literallayout"><a name="id-1_3_14_15_3_59_1_1_1_7-bb"></a><span class="identifier">wrapping_int</span><span class="special">(</span><span class="identifier">int_type</span> v<span class="special">)</span><span class="special">;</span></pre>Add, return true if wrapped. </li></ol></div> 68</div> 69<div class="refsect2"> 70<a name="id-1.3.14.15.3.58.3.4.6"></a><h3> 71<a name="id-1_3_14_15_3_59_1_1_1_5-bb"></a><code class="computeroutput">wrapping_int</code> public static functions</h3> 72<div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><pre class="literallayout"><span class="keyword">static</span> <span class="identifier">BOOST_CONSTEXPR</span> <span class="identifier">int_type</span> <a name="id-1_3_14_15_3_59_1_1_1_5_1-bb"></a><span class="identifier">wrap_value</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre></li></ol></div> 73</div> 74<div class="refsect2"> 75<a name="id-1.3.14.15.3.58.3.4.7"></a><h3> 76<a name="id-1_3_14_15_3_59_1_1_1_6-bb"></a><code class="computeroutput">wrapping_int</code> public member functions</h3> 77<div class="orderedlist"><ol class="orderedlist" type="1"> 78<li class="listitem"> 79<pre class="literallayout"><span class="identifier">BOOST_CONSTEXPR</span> <span class="identifier">int_type</span> <a name="id-1_3_14_15_3_59_1_1_1_6_1-bb"></a><span class="identifier">as_int</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre>Explicit converion method. </li> 80<li class="listitem"><pre class="literallayout"><span class="identifier">BOOST_CONSTEXPR</span> <a name="id-1_3_14_15_3_59_1_1_1_6_2-bb"></a><span class="keyword">operator</span> <span class="identifier">int_type</span><span class="special">(</span><span class="special">)</span> <span class="keyword">const</span><span class="special">;</span></pre></li> 81<li class="listitem"> 82<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> IntT<span class="special">></span> <span class="identifier">BOOST_CXX14_CONSTEXPR</span> <span class="identifier">IntT</span> <a name="id-1_3_14_15_3_59_1_1_1_6_3-bb"></a><span class="identifier">add</span><span class="special">(</span><span class="identifier">IntT</span> v<span class="special">)</span><span class="special">;</span></pre>Add, return number of wraps performed. <p>The sign of the returned value will indicate which direction the wraps went. Ex: add a negative number and wrapping under could occur, this would be indicated by a negative return value. If wrapping over took place, a positive value would be returned </p> 83</li> 84<li class="listitem"> 85<pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> IntT<span class="special">></span> <span class="identifier">BOOST_CXX14_CONSTEXPR</span> <span class="identifier">IntT</span> <a name="id-1_3_14_15_3_59_1_1_1_6_4-bb"></a><span class="identifier">subtract</span><span class="special">(</span><span class="identifier">IntT</span> v<span class="special">)</span><span class="special">;</span></pre>Subtract will return '+d' if wrapping under took place ('d' is the number of wraps) <p>The sign of the returned value will indicate which direction the wraps went (positive indicates wrap under, negative indicates wrap over). Ex: subtract a negative number and wrapping over could occur, this would be indicated by a negative return value. If wrapping under took place, a positive value would be returned. </p> 86</li> 87</ol></div> 88</div> 89<div class="refsect2"> 90<a name="id-1.3.14.15.3.58.3.4.8"></a><h3> 91<a name="id-1_3_14_15_3_59_1_1_1_8-bb"></a><code class="computeroutput">wrapping_int</code> private member functions</h3> 92<div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><pre class="literallayout"><span class="keyword">template</span><span class="special"><</span><span class="keyword">typename</span> IntT<span class="special">></span> <span class="identifier">BOOST_CXX14_CONSTEXPR</span> <span class="identifier">IntT</span> <a name="id-1_3_14_15_3_59_1_1_1_8_1-bb"></a><span class="identifier">calculate_wrap</span><span class="special">(</span><span class="identifier">IntT</span> wrap<span class="special">)</span><span class="special">;</span></pre></li></ol></div> 93</div> 94</div> 95</div> 96<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 97<td align="left"></td> 98<td align="right"><div class="copyright-footer">Copyright © 2001-2005 CrystalClear Software, Inc<p>Subject to the Boost Software License, Version 1.0. (See accompanying file 99 <code class="filename">LICENSE_1_0.txt</code> or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)</p> 100</div></td> 101</tr></table> 102<hr> 103<div class="spirit-nav"> 104<a accesskey="p" href="tz_db_base.html"><img src="../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../../date_time/doxy.html#header.boost.date_time.wrapping_int_hpp"><img src="../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="wrapping_int2.html"><img src="../../../../doc/src/images/next.png" alt="Next"></a> 105</div> 106</body> 107</html> 108
