boost-react-native-bundle

<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=US-ASCII"> <title>Reference</title> <link rel="stylesheet" href="../../../doc/src/boostbook.css" type="text/css"> <meta name="generator" content="DocBook XSL Stylesheets V1.78.1"> <link rel="home" href="../index.html" title="The Boost C++ Libraries BoostBook Documentation Subset"> <link rel="up" href="../chrono.html" title="Chapter 6. Boost.Chrono 2.0.4"> <link rel="prev" href="users_guide.html" title="User's Guide"> <link rel="next" href="appendices.html" title="Appendices"> </head> <body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> <table cellpadding="2" width="100%"><tr> <td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../boost.png"></td> <td align="center"><a href="../../../index.html">Home</a></td> <td align="center"><a href="../../../libs/libraries.htm">Libraries</a></td> <td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> <td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> <td align="center"><a href="../../../more/index.htm">More</a></td> </tr></table> <hr> <div class="spirit-nav"> <a accesskey="p" href="users_guide.html"><img src="../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../chrono.html"><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="appendices.html"><img src="../../../doc/src/images/next.png" alt="Next"></a> </div> <div class="section"> <div class="titlepage"><div><div><h2 class="title" style="clear: both"> <a name="chrono.reference"></a><a class="link" href="reference.html" title="Reference">Reference </a> </h2></div></div></div> <div class="toc"><dl class="toc"> <dt><a href="reference.html#chrono.reference.chrono_include_hpp">Header <code class="computeroutput"><boost/chrono/include.hpp></code></a></dt> <dt><a href="reference.html#chrono.reference.cpp0x">Included on the C++11 Recommendation</a></dt> <dt><a href="reference.html#chrono.reference.io_v1">Chrono I/O V1</a></dt> <dt><a href="reference.html#chrono.reference.io">Chrono I/O V2</a></dt> <dt><a href="reference.html#chrono.reference.round">Chrono Rounding Utilities</a></dt> <dt><a href="reference.html#chrono.reference.other_clocks">Other Clocks</a></dt> </dl></div> As <code class="computeroutput">constexpr</code> will not be supported by some compilers, it is replaced in the code by <code class="computeroutput">BOOST_CONSTEXPR</code> for <code class="computeroutput">constexpr</code> functions and <code class="computeroutput">BOOST_STATIC_CONSTEXPR</code> for struct/class static fields. The same applies to <code class="computeroutput">noexecpt</code> which is replaced by <code class="computeroutput">noexcept</code> in the code. The documentation doesn't use these macros. <div class="section"> <div class="titlepage"><div><div><h3 class="title"> <a name="chrono.reference.chrono_include_hpp"></a><a class="link" href="reference.html#chrono.reference.chrono_include_hpp" title="Header <boost/chrono/include.hpp>">Header <code class="computeroutput"><boost/chrono/include.hpp></code></a> </h3></div></div></div> Include all the chrono header files. <pre class="programlisting">#include <boost/chrono/chrono.hpp> #include <boost/chrono/chrono_io.hpp> #include <boost/chrono/process_cpu_clocks.hpp> #include <boost/chrono/thread_clocks.hpp> #include <boost/chrono/ceil.hpp> #include <boost/chrono/floor.hpp> #include <boost/chrono/round.hpp> </pre> </div> <div class="section"> <div class="titlepage"><div><div><h3 class="title"> <a name="chrono.reference.cpp0x"></a><a class="link" href="reference.html#chrono.reference.cpp0x" title="Included on the C++11 Recommendation">Included on the C++11 Recommendation</a> </h3></div></div></div> <div class="toc"><dl class="toc"> <dt><a href="reference.html#chrono.reference.cpp0x.chrono_hpp">Header <code class="computeroutput"><boost/chrono.hpp></code></a></dt> <dt><a href="reference.html#chrono.reference.cpp0x.chrono_chrono_hpp">Header <code class="computeroutput"><boost/chrono/chrono.hpp></code></a></dt> <dt><a href="reference.html#chrono.reference.cpp0x.duration_hpp">Header <code class="computeroutput"><boost/chrono/duration.hpp></code></a></dt> <dt><a href="reference.html#chrono.reference.cpp0x.clock"><code class="computeroutput">Clock</code> Requirements</a></dt> <dt><a href="reference.html#chrono.reference.cpp0x.trivial_clock"><code class="computeroutput">TrivialClock</code> Requirements</a></dt> <dt><a href="reference.html#chrono.reference.cpp0x.ecclock"><code class="computeroutput">EcClock</code> Requirements</a></dt> <dt><a href="reference.html#chrono.reference.cpp0x.time_point_hpp">Header <code class="computeroutput"><boost/chrono/time_point.hpp></code></a></dt> <dt><a href="reference.html#chrono.reference.cpp0x.system_clocks_hpp">Header <code class="computeroutput"><boost/chrono/system_clocks.hpp></code></a></dt> <dt><a href="reference.html#chrono.reference.cpp0x.clock_strings_hpp">Header <code class="computeroutput"><boost/chrono/clock_strings.hpp></code></a></dt> <dt><a href="reference.html#chrono.reference.cpp0x.chrono_typeof_hpp">Header <code class="computeroutput"><boost/chrono/typeof/boost/chrono/chrono.hpp></code></a></dt> </dl></div> <div class="section"> <div class="titlepage"><div><div><h4 class="title"> <a name="chrono.reference.cpp0x.chrono_hpp"></a><a class="link" href="reference.html#chrono.reference.cpp0x.chrono_hpp" title="Header <boost/chrono.hpp>">Header <code class="computeroutput"><boost/chrono.hpp></code></a> </h4></div></div></div> Include only the standard files. <pre class="programlisting">#include <boost/chrono/chrono.hpp> </pre> </div> <div class="section"> <div class="titlepage"><div><div><h4 class="title"> <a name="chrono.reference.cpp0x.chrono_chrono_hpp"></a><a class="link" href="reference.html#chrono.reference.cpp0x.chrono_chrono_hpp" title="Header <boost/chrono/chrono.hpp>">Header <code class="computeroutput"><boost/chrono/chrono.hpp></code></a> </h4></div></div></div> <div class="toc"><dl class="toc"> <dt><a href="reference.html#chrono.reference.cpp0x.chrono_chrono_hpp.limitations">Limitations and Extensions</a></dt> <dt><a href="reference.html#chrono.reference.cpp0x.chrono_chrono_hpp.conf">Configuration Macros</a></dt> </dl></div> Include only the standard files. <pre class="programlisting">#include <boost/chrono/duration.hpp> #include <boost/chrono/time_point.hpp> #include <boost/chrono/system_clocks.hpp> #include <boost/chrono/typeof/boost/chrono/chrono.hpp> </pre> <div class="section"> <div class="titlepage"><div><div><h5 class="title"> <a name="chrono.reference.cpp0x.chrono_chrono_hpp.limitations"></a><a class="link" href="reference.html#chrono.reference.cpp0x.chrono_chrono_hpp.limitations" title="Limitations and Extensions">Limitations and Extensions</a> </h5></div></div></div> At present, tthere is no know limitation respect to the C++11 standard. The current implementation provides in addition: <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> <li class="listitem"> clock error handling as specified in <a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2010/n3135.html#935" target="_top">clock error handling needs to be specified</a>. </li> <li class="listitem"> process and thread clocks. </li> </ul></div> </div> <div class="section"> <div class="titlepage"><div><div><h5 class="title"> <a name="chrono.reference.cpp0x.chrono_chrono_hpp.conf"></a><a class="link" href="reference.html#chrono.reference.cpp0x.chrono_chrono_hpp.conf" title="Configuration Macros">Configuration Macros</a> </h5></div></div></div> <div class="section"> <div class="titlepage"><div><div><h6 class="title"> <a name="chrono.reference.cpp0x.chrono_chrono_hpp.conf.assert"></a><a class="link" href="reference.html#chrono.reference.cpp0x.chrono_chrono_hpp.conf.assert" title="How Assert Behaves?">How Assert Behaves?</a> </h6></div></div></div> When <code class="computeroutput">BOOST_NO_STATIC_ASSERT</code> is defined, the user can select the way static assertions are reported. Define <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> <li class="listitem"> <code class="computeroutput">BOOST_CHRONO_USES_STATIC_ASSERT</code>: define it if you want to use Boost.StaticAssert. </li> <li class="listitem"> <code class="computeroutput">BOOST_CHRONO_USES_MPL_ASSERT</code>: define it if you want to use Boost.MPL static asertions. </li> <li class="listitem"> <code class="computeroutput">BOOST_CHRONO_USES_ARRAY_ASSERT</code>: define it if you want to use internal static asertions. </li> </ul></div> The default behavior is as <code class="computeroutput">BOOST_CHRONO_USES_ARRAY_ASSERT</code> was defined. When <code class="computeroutput">BOOST_CHRONO_USES_MPL_ASSERT</code> is not defined the following symbols are defined as <pre class="programlisting">#define BOOST_CHRONO_A_DURATION_REPRESENTATION_CAN_NOT_BE_A_DURATION \ "A duration representation can not be a duration" #define BOOST_CHRONO_SECOND_TEMPLATE_PARAMETER_OF_DURATION_MUST_BE_A_STD_RATIO \ "Second template parameter of duration must be a boost::ratio" #define BOOST_CHRONO_DURATION_PERIOD_MUST_BE_POSITIVE \ "duration period must be positive" #define BOOST_CHRONO_SECOND_TEMPLATE_PARAMETER_OF_TIME_POINT_MUST_BE_A_BOOST_CHRONO_DURATION \ "Second template parameter of time_point must be a boost::chrono::duration" </pre> Depending on the static assertion used system you will have an hint of the failing assertion either through the symbol or through the text. </div> <div class="section"> <div class="titlepage"><div><div><h6 class="title"> <a name="chrono.reference.cpp0x.chrono_chrono_hpp.conf.no_hybrid"></a><a class="link" href="reference.html#chrono.reference.cpp0x.chrono_chrono_hpp.conf.no_hybrid" title="Don't provide Hybrid Error Handling">Don't provide Hybrid Error Handling</a> </h6></div></div></div> When <code class="computeroutput">BOOST_CHRONO_DONT_PROVIDE_HYBRID_ERROR_HANDLING</code> is defined the lib don't provides the hybrid error handling prototypes: <pre class="programlisting">Clock::time_point Clock::now(system::error_code&ec=boost::throws()); </pre> This allow to be closer to the standard and to avoid the Boost.System dependency, making possible to have Boost.Chrono as a header-only library. By default <code class="computeroutput">BOOST_CHRONO_PROVIDE_HYBRID_ERROR_HANDLING</code> is defined. </div> <div class="section"> <div class="titlepage"><div><div><h6 class="title"> <a name="chrono.reference.cpp0x.chrono_chrono_hpp.conf.header_only"></a><a class="link" href="reference.html#chrono.reference.cpp0x.chrono_chrono_hpp.conf.header_only" title="How to Build Boost.Chrono as a Header Only Library?">How to Build Boost.Chrono as a Header Only Library?</a> </h6></div></div></div> When <code class="computeroutput">BOOST_CHRONO_HEADER_ONLY</code> is defined the lib is header-only. If in addition <code class="computeroutput">BOOST_USE_WINDOWS_H</code> is defined <code class="computeroutput"><windows.h></code> is included, otherwise files in <code class="computeroutput">boost/detail/win</code> are used to reduce the impact of including <code class="computeroutput"><windows.h></code>. However, you will either need to define <code class="computeroutput">BOOST_CHRONO_DONT_PROVIDE_HYBRID_ERROR_HANDLING</code> or link with Boost.System. </div> <div class="section"> <div class="titlepage"><div><div><h6 class="title"> <a name="chrono.reference.cpp0x.chrono_chrono_hpp.conf.deprecated_io"></a><a class="link" href="reference.html#chrono.reference.cpp0x.chrono_chrono_hpp.conf.deprecated_io" title="Deprecated IO">Deprecated IO</a> </h6></div></div></div> Version 2.0.0 deprecates the preceding IO features. These deprecated features will be provided by default up to boost 1.55. If you don't want to include the deprecated features you could define <code class="computeroutput">BOOST_CHRONO_DONT_PROVIDES_DEPRECATED_IO_SINCE_V2_0_0</code>. Since 1.55 these features will not be included any more by default. Since this version, if you want to include the deprecated features yet you could define <code class="computeroutput">BOOST_CHRONO_PROVIDES_DEPRECATED_IO_SINCE_V2_0_0</code>. These deprecated features will be only available until boost 1.58, that is you have 1 year and a half to move to the new features. </div> <div class="section"><div class="titlepage"><div><div><h6 class="title"> <a name="chrono.reference.cpp0x.chrono_chrono_hpp.conf.system_clock_time_point"></a><a class="link" href="reference.html#chrono.reference.cpp0x.chrono_chrono_hpp.conf.system_clock_time_point" title="time_point<system_clock,D> specialization limitation">time_point<system_clock,D> specialization limitation</a> </h6></div></div></div></div> <div class="section"> <div class="titlepage"><div><div><h6 class="title"> <a name="chrono.reference.cpp0x.chrono_chrono_hpp.conf.version"></a><a class="link" href="reference.html#chrono.reference.cpp0x.chrono_chrono_hpp.conf.version" title="Version">Version</a> </h6></div></div></div> <code class="computeroutput">BOOST_CHRONO_VERSION</code> defines the Boost.Chrono version. The default version is 1. In this case the following breaking or extending macros are defined if the opposite is not requested: <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"> <code class="computeroutput">BOOST_CHRONO_PROVIDES_DEPRECATED_IO_SINCE_V2_0_0</code> </li></ul></div> The user can request the version 2 by defining <code class="computeroutput">BOOST_CHRONO_VERSION</code> to 2. In this case the following breaking or extending macros are defined if the opposite is not requested: <div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"> Breaking change <code class="computeroutput">BOOST_CHRONO_DONT_PROVIDES_DEPRECATED_IO_SINCE_V2_0_0 </code> </li></ul></div> The default value for <code class="computeroutput">BOOST_CHRONO_VERSION</code> will be changed to 2 since Boost 1.55. </div> </div> </div> <div class="section"> <div class="titlepage"><div><div><h4 class="title"> <a name="chrono.reference.cpp0x.duration_hpp"></a><a class="link" href="reference.html#chrono.reference.cpp0x.duration_hpp" title="Header <boost/chrono/duration.hpp>">Header <code class="computeroutput"><boost/chrono/duration.hpp></code></a> </h4></div></div></div> <div class="toc"><dl class="toc"> <dt><a href="reference.html#chrono.reference.cpp0x.duration_hpp.traits">Time-related Traits</a></dt> <dt><a href="reference.html#chrono.reference.cpp0x.duration_hpp.common_type_spe"><code class="computeroutput">common_type</code> Specialization</a></dt> <dt><a href="reference.html#chrono.reference.cpp0x.duration_hpp.duration">Class Template <code class="computeroutput">duration<></code></a></dt> <dt><a href="reference.html#chrono.reference.cpp0x.duration_hpp.arith"><code class="computeroutput">duration</code> Non-Member Arithmetic</a></dt> <dt><a href="reference.html#chrono.reference.cpp0x.duration_hpp.cmp"><code class="computeroutput">duration</code> Non-Member Comparaisons</a></dt> <dt><a href="reference.html#chrono.reference.cpp0x.duration_hpp.duration_cast">Non-Member Function <code class="computeroutput">duration_cast(duration)</code></a></dt> <dt><a href="reference.html#chrono.reference.cpp0x.duration_hpp.duration_typedefs"><code class="computeroutput">duration</code> typedefs</a></dt> </dl></div> This file contains duration specific classes and non-member functions. <pre class="programlisting">namespace boost { namespace chrono { template <class Rep, class Period = <code class="computeroutput">ratio</code><1> > class <a class="link" href="reference.html#chrono.reference.cpp0x.duration_hpp.duration" title="Class Template duration<>"><code class="computeroutput">duration</code></a>; } template <class Rep1, class Period1, class Rep2, class Period2> struct <a class="link" href="reference.html#chrono.reference.cpp0x.duration_hpp.common_type_spe" title="common_type Specialization"><code class="computeroutput">common_type</code></a><duration<Rep1, Period1>, duration<Rep2, Period2> >; namespace chrono { // customization traits template <class Rep> struct <a class="link" href="reference.html#chrono.reference.cpp0x.duration_hpp.traits.treat_as_floating_point" title="Metafunction treat_as_floating_point<>"><code class="computeroutput">treat_as_floating_point</code></a>; template <class Rep> struct <a class="link" href="reference.html#chrono.reference.cpp0x.duration_hpp.traits.duration_values" title="Class Template duration_values"><code class="computeroutput">duration_values</code></a>; // duration arithmetic template <class Rep1, class Period1, class Rep2, class Period2> constexpr typename common_type<duration<Rep1, Period1>, duration<Rep2, Period2> >::type <a class="link" href="reference.html#chrono.reference.cpp0x.duration_hpp.arith.duration__op_plus_1" title="Non-Member Function operator+(duration,duration)"><code class="computeroutput">operator+</code></a>( const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs); template <class Rep1, class Period1, class Rep2, class Period2> constexpr typename common_type<duration<Rep1, Period1>, duration<Rep2, Period2> >::type <a class="link" href="reference.html#chrono.reference.cpp0x.duration_hpp.arith.duration__op_minus_1" title="Non-Member Function operator-(duration,duration)"><code class="computeroutput">operator-</code></a>( const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs); template <class Rep1, class Period, class Rep2> constexpr duration<typename common_type<Rep1, Rep2>::type, Period> <a class="link" href="reference.html#chrono.reference.cpp0x.duration_hpp.arith.duration__op_mult_1" title="Non-Member Function operator*(duration,Rep1)"><code class="computeroutput">operator*</code></a>( const duration<Rep1, Period>& d, const Rep2& s); template <class Rep1, class Period, class Rep2> constexpr duration<typename common_type<Rep1, Rep2>::type, Period> <a class="link" href="reference.html#chrono.reference.cpp0x.duration_hpp.arith.duration__op_mult_2" title="Non-Member Function operator*(Rep1,duration)"><code class="computeroutput">operator*</code></a>( const Rep1& s, const duration<Rep2, Period>& d); template <class Rep1, class Period, class Rep2> constexpr duration<typename common_type<Rep1, Rep2>::type, Period> <a class="link" href="reference.html#chrono.reference.cpp0x.duration_hpp.arith.duration__op_div_2" title="Non-Member Function operator/(duration,duration)"><code class="computeroutput">operator/</code></a>( const duration<Rep1, Period>& d, const Rep2& s); template <class Rep1, class Period1, class Rep2, class Period2> constexpr typename common_type<Rep1, Rep2>::type <a class="link" href="reference.html#chrono.reference.cpp0x.duration_hpp.arith.duration__op_div_3" title="Non-Member Function operator/(Rep1,duration)"><code class="computeroutput">operator/</code></a>( const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs); #ifdef BOOST_CHRONO_EXTENSIONS // Used to get frecuency of events template <class Rep1, class Rep2, class Period> constexpr double <a class="link" href="reference.html#chrono.reference.cpp0x.duration_hpp.arith.duration__op_div_1" title="Non-Member Function operator/(duration,Rep2)"><code class="computeroutput">operator/</code></a>( const Rep1& s, const duration<Rep2, Period>& d); #endif // duration comparisons template <class Rep1, class Period1, class Rep2, class Period2> constexpr bool <a class="link" href="reference.html#chrono.reference.cpp0x.duration_hpp.cmp.duration__op_eq_1" title="Non-Member Function operator==(duration,duration)"><code class="computeroutput">operator==</code></a>( const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs); template <class Rep1, class Period1, class Rep2, class Period2> constexpr bool <a class="link" href="reference.html#chrono.reference.cpp0x.duration_hpp.cmp.duration__op_neq_1" title="Non-Member Function operator!=(duration,duration)"><code class="computeroutput">operator!=</code></a>( const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs); template <class Rep1, class Period1, class Rep2, class Period2> constexpr bool __duration__op_le_1( const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs); template <class Rep1, class Period1, class Rep2, class Period2> constexpr bool <a class="link" href="reference.html#chrono.reference.cpp0x.duration_hpp.cmp.duration__op_leq_1" title="Non-Member Function operator<=(duration,duration)"><code class="computeroutput">operator<=</code></a>( const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs<span class="special"