2004-11-28 03:35:12 +00:00
<?xml version="1.0" encoding="utf-8" ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
< html xmlns = "http://www.w3.org/1999/xhtml" xml:lang = "en" lang = "en" >
< head >
< meta http-equiv = "Content-Type" content = "text/html; charset=utf-8" / >
2010-08-09 20:07:24 +00:00
< meta name = "generator" content = "Docutils 0.7: http://docutils.sourceforge.net/" / >
2004-11-28 03:35:12 +00:00
< title > The MPL Reference Manual: numeric_cast< / title >
< link rel = "stylesheet" href = "../style.css" type = "text/css" / >
< / head >
< body class = "docframe refmanual" >
< table class = "header" > < tr class = "header" > < td class = "header-group navigation-bar" > < span class = "navigation-group" > < a href = "./inherit-linearly.html" class = "navigation-link" > Prev< / a > < a href = "./min.html" class = "navigation-link" > Next< / a > < / span > < span class = "navigation-group-separator" > | < / span > < span class = "navigation-group" > < a href = "./inherit-linearly.html" class = "navigation-link" > Back< / a > < a href = "./min.html" class = "navigation-link" > Along< / a > < / span > < span class = "navigation-group-separator" > | < / span > < span class = "navigation-group" > < a href = "./miscellaneous.html" class = "navigation-link" > Up< / a > < a href = "../refmanual.html" class = "navigation-link" > Home< / a > < / span > < span class = "navigation-group-separator" > | < / span > < span class = "navigation-group" > < a href = "./refmanual_toc.html" class = "navigation-link" > Full TOC< / a > < / span > < / td >
< td class = "header-group page-location" > < a href = "../refmanual.html" class = "navigation-link" > Front Page< / a > / < a href = "./metafunctions.html" class = "navigation-link" > Metafunctions< / a > / < a href = "./miscellaneous.html" class = "navigation-link" > Miscellaneous< / a > / < a href = "./numeric-cast.html" class = "navigation-link" > numeric_cast< / a > < / td >
< / tr > < / table > < div class = "header-separator" > < / div >
< div class = "section" id = "numeric-cast" >
2010-08-09 20:07:24 +00:00
< h1 > < a class = "toc-backref" href = "./miscellaneous.html#id1568" > numeric_cast< / a > < / h1 >
2009-08-17 11:30:52 +00:00
< div class = "section" id = "id1181" >
2004-11-28 03:35:12 +00:00
< h3 > < a class = "subsection-title" href = "#synopsis" name = "synopsis" > Synopsis< / a > < / h3 >
< pre class = "literal-block" >
2009-08-17 11:30:52 +00:00
template<
2004-11-28 03:35:12 +00:00
typename SourceTag
, typename TargetTag
>
struct < a href = "./numeric-cast.html" class = "identifier" > numeric_cast< / a > ;
< / pre >
< / div >
2009-08-17 11:30:52 +00:00
< div class = "section" id = "id1182" >
2004-11-28 03:35:12 +00:00
< h3 > < a class = "subsection-title" href = "#description" name = "description" > Description< / a > < / h3 >
2009-08-17 11:30:52 +00:00
< p > Each < tt class = "literal" > < span class = "pre" > < a href = "./numeric-cast.html" class = "identifier" > numeric_cast< / a > < / span > < / tt > specialization is a user-specialized unary < a class = "reference internal" href = "./metafunction-class.html" > Metafunction Class< / a >
2004-11-28 03:35:12 +00:00
providing a conversion between two numeric types.< / p >
< / div >
2009-08-17 11:30:52 +00:00
< div class = "section" id = "id1183" >
2004-11-28 03:35:12 +00:00
< h3 > < a class = "subsection-title" href = "#header" name = "header" > Header< / a > < / h3 >
< pre class = "literal-block" >
#include < < a href = "../../../../boost/mpl/numeric_cast.hpp" class = "header" > boost/mpl/numeric_cast.hpp< / a > >
< / pre >
< / div >
2009-08-17 11:30:52 +00:00
< div class = "section" id = "id1184" >
2004-11-28 03:35:12 +00:00
< h3 > < a class = "subsection-title" href = "#parameters" name = "parameters" > Parameters< / a > < / h3 >
2009-08-17 11:30:52 +00:00
< table border = "1" class = "docutils table" >
2004-11-28 03:35:12 +00:00
< colgroup >
< col width = "17%" / >
< col width = "30%" / >
< col width = "53%" / >
< / colgroup >
< thead valign = "bottom" >
2009-08-17 11:30:52 +00:00
< tr > < th class = "head" > Parameter< / th >
< th class = "head" > Requirement< / th >
< th class = "head" > Description< / th >
2004-11-28 03:35:12 +00:00
< / tr >
< / thead >
< tbody valign = "top" >
< tr > < td > < tt class = "literal" > < span class = "pre" > SourceTag< / span > < / tt > < / td >
2009-08-17 11:30:52 +00:00
< td > < a class = "reference internal" href = "./integral-constant.html" > Integral Constant< / a > < / td >
2004-11-28 03:35:12 +00:00
< td > A tag for the conversion's source type.< / td >
< / tr >
< tr > < td > < tt class = "literal" > < span class = "pre" > TargetTag< / span > < / tt > < / td >
2009-08-17 11:30:52 +00:00
< td > < a class = "reference internal" href = "./integral-constant.html" > Integral Constant< / a > < / td >
2004-11-28 03:35:12 +00:00
< td > A tag for the conversion's destination type.< / td >
< / tr >
< / tbody >
< / table >
< / div >
2009-08-17 11:30:52 +00:00
< div class = "section" id = "id1185" >
2004-11-28 03:35:12 +00:00
< h3 > < a class = "subsection-title" href = "#expression-semantics" name = "expression-semantics" > Expression semantics< / a > < / h3 >
2009-08-17 11:30:52 +00:00
< p > If < tt class = "literal" > < span class = "pre" > x< / span > < / tt > and < tt class = "literal" > < span class = "pre" > y< / span > < / tt > are two numeric types, < tt class = "literal" > < span class = "pre" > x< / span > < / tt > is convertible to < tt class = "literal" > < span class = "pre" > y< / span > < / tt > , and
< tt class = "literal" > < span class = "pre" > x_tag< / span > < / tt > and < tt class = "literal" > < span class = "pre" > y_tag< / span > < / tt > are the types' corresponding < a class = "reference internal" href = "./integral-constant.html" > Integral Constant< / a > tags:< / p >
2004-11-28 03:35:12 +00:00
< pre class = "literal-block" >
typedef < a href = "./apply-wrap.html" class = "identifier" > apply_wrap< / a > < tt class = "literal" > < span class = "pre" > 2< / span > < / tt > < < a href = "./numeric-cast.html" class = "identifier" > numeric_cast< / a > < x_tag,y_tag> ,x > ::type r;
< / pre >
2009-08-17 11:30:52 +00:00
< table class = "docutils field-list" frame = "void" rules = "none" >
2004-11-28 03:35:12 +00:00
< col class = "field-name" / >
< col class = "field-body" / >
< tbody valign = "top" >
< tr class = "field" > < th class = "field-name" > Return type:< / th > < td class = "field-body" > A type.< / td >
< / tr >
< tr class = "field" > < th class = "field-name" > Semantics:< / th > < td class = "field-body" > < tt class = "literal" > < span class = "pre" > r< / span > < / tt > is a value of < tt class = "literal" > < span class = "pre" > x< / span > < / tt > converted to the type of < tt class = "literal" > < span class = "pre" > y< / span > < / tt > .< / td >
< / tr >
< / tbody >
< / table >
< / div >
2009-08-17 11:30:52 +00:00
< div class = "section" id = "id1186" >
2004-11-28 03:35:12 +00:00
< h3 > < a class = "subsection-title" href = "#complexity" name = "complexity" > Complexity< / a > < / h3 >
< p > Unspecified.< / p >
< / div >
2009-08-17 11:30:52 +00:00
< div class = "section" id = "id1187" >
2004-11-28 03:35:12 +00:00
< h3 > < a class = "subsection-title" href = "#example" name = "example" > Example< / a > < / h3 >
< pre class = "literal-block" >
struct complex_tag : < a href = "./int.html" class = "identifier" > int_< / a > < 10> {};
template< typename Re, typename Im > struct complex
{
typedef complex_tag tag;
typedef complex type;
typedef Re real;
typedef Im imag;
};
template< typename C > struct real : C::real {};
template< typename C > struct imag : C::imag {};
namespace boost { namespace mpl {
template< > struct < a href = "./numeric-cast.html" class = "identifier" > numeric_cast< / a > < integral_c_tag,complex_tag >
{
template< typename N > struct < a href = "./apply.html" class = "identifier" > apply< / a >
: complex< N, < a href = "./integral-c.html" class = "identifier" > integral_c< / a > < typename N::< a href = "./value-type.html" class = "identifier" > value_type< / a > , 0 > >
{
};
};
template< >
struct plus_impl< complex_tag,complex_tag >
{
template< typename N1, typename N2 > struct < a href = "./apply.html" class = "identifier" > apply< / a >
: complex<
< a href = "./plus.html" class = "identifier" > plus< / a > < typename N1::real, typename N2::real >
, < a href = "./plus.html" class = "identifier" > plus< / a > < typename N1::imag, typename N2::imag >
>
{
};
};
}}
typedef < a href = "./int.html" class = "identifier" > int_< / a > < 2> i;
typedef complex< < a href = "./int.html" class = "identifier" > int_< / a > < 5> , < a href = "./int.html" class = "identifier" > int_< / a > < -1> > c1;
typedef complex< < a href = "./int.html" class = "identifier" > int_< / a > < -5> , < a href = "./int.html" class = "identifier" > int_< / a > < 1> > c2;
typedef < a href = "./plus.html" class = "identifier" > plus< / a > < c1,i> r4;
< a href = "./assert-relation.html" class = "identifier" > BOOST_MPL_ASSERT_RELATION< / a > ( real< r4> ::value, ==, 7 );
< a href = "./assert-relation.html" class = "identifier" > BOOST_MPL_ASSERT_RELATION< / a > ( imag< r4> ::value, ==, -1 );
typedef < a href = "./plus.html" class = "identifier" > plus< / a > < i,c2> r5;
< a href = "./assert-relation.html" class = "identifier" > BOOST_MPL_ASSERT_RELATION< / a > ( real< r5> ::value, ==, -3 );
< a href = "./assert-relation.html" class = "identifier" > BOOST_MPL_ASSERT_RELATION< / a > ( imag< r5> ::value, ==, 1 );
< / pre >
< / div >
2009-08-17 11:30:52 +00:00
< div class = "section" id = "id1188" >
2004-11-28 03:35:12 +00:00
< h3 > < a class = "subsection-title" href = "#see-also" name = "see-also" > See also< / a > < / h3 >
2009-08-17 11:30:52 +00:00
< p > < a class = "reference internal" href = "./metafunctions.html" > Metafunctions< / a > , < a class = "reference internal" href = "./numeric-metafunction.html" > Numeric Metafunction< / a > , < a class = "reference internal" href = "./plus.html" > plus< / a > , < a class = "reference internal" href = "./minus.html" > minus< / a > , < a class = "reference internal" href = "./times.html" > times< / a > < / p >
2004-11-28 03:35:12 +00:00
<!-- Metafunctions/Miscellaneous//min |80 -->
< / div >
< / div >
< div class = "footer-separator" > < / div >
< table class = "footer" > < tr class = "footer" > < td class = "header-group navigation-bar" > < span class = "navigation-group" > < a href = "./inherit-linearly.html" class = "navigation-link" > Prev< / a > < a href = "./min.html" class = "navigation-link" > Next< / a > < / span > < span class = "navigation-group-separator" > | < / span > < span class = "navigation-group" > < a href = "./inherit-linearly.html" class = "navigation-link" > Back< / a > < a href = "./min.html" class = "navigation-link" > Along< / a > < / span > < span class = "navigation-group-separator" > | < / span > < span class = "navigation-group" > < a href = "./miscellaneous.html" class = "navigation-link" > Up< / a > < a href = "../refmanual.html" class = "navigation-link" > Home< / a > < / span > < span class = "navigation-group-separator" > | < / span > < span class = "navigation-group" > < a href = "./refmanual_toc.html" class = "navigation-link" > Full TOC< / a > < / span > < / td >
2009-08-17 11:30:52 +00:00
< td > < div class = "copyright-footer" > < div class = "copyright" > Copyright © 2001-2009 Aleksey Gurtovoy and David Abrahams< / div >
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at < a class = "reference external" href = "http://www.boost.org/LICENSE_1_0.txt" target = "_top" > http://www.boost.org/LICENSE_1_0.txt< / a > )< / div > < / td > < / tr > < / table > < / body >
2004-11-28 03:35:12 +00:00
< / html >
