annotate DEPENDENCIES/generic/include/boost/cast.hpp @ 16:2665513ce2d3

Add boost headers
author Chris Cannam
date Tue, 05 Aug 2014 11:11:38 +0100
parents
children c530137014c0
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Chris@16 1 // boost cast.hpp header file ----------------------------------------------//
Chris@16 2
Chris@16 3 // (C) Copyright Kevlin Henney and Dave Abrahams 1999.
Chris@16 4 // Distributed under the Boost
Chris@16 5 // Software License, Version 1.0. (See accompanying file
Chris@16 6 // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
Chris@16 7
Chris@16 8 // See http://www.boost.org/libs/conversion for Documentation.
Chris@16 9
Chris@16 10 // Revision History
Chris@16 11 // 23 JUn 05 numeric_cast removed and redirected to the new verion (Fernando Cacciola)
Chris@16 12 // 02 Apr 01 Removed BOOST_NO_LIMITS workarounds and included
Chris@16 13 // <boost/limits.hpp> instead (the workaround did not
Chris@16 14 // actually compile when BOOST_NO_LIMITS was defined in
Chris@16 15 // any case, so we loose nothing). (John Maddock)
Chris@16 16 // 21 Jan 01 Undid a bug I introduced yesterday. numeric_cast<> never
Chris@16 17 // worked with stock GCC; trying to get it to do that broke
Chris@16 18 // vc-stlport.
Chris@16 19 // 20 Jan 01 Moved BOOST_NO_LIMITS_COMPILE_TIME_CONSTANTS to config.hpp.
Chris@16 20 // Removed unused BOOST_EXPLICIT_TARGET macro. Moved
Chris@16 21 // boost::detail::type to boost/type.hpp. Made it compile with
Chris@16 22 // stock gcc again (Dave Abrahams)
Chris@16 23 // 29 Nov 00 Remove nested namespace cast, cleanup spacing before Formal
Chris@16 24 // Review (Beman Dawes)
Chris@16 25 // 19 Oct 00 Fix numeric_cast for floating-point types (Dave Abrahams)
Chris@16 26 // 15 Jul 00 Suppress numeric_cast warnings for GCC, Borland and MSVC
Chris@16 27 // (Dave Abrahams)
Chris@16 28 // 30 Jun 00 More MSVC6 wordarounds. See comments below. (Dave Abrahams)
Chris@16 29 // 28 Jun 00 Removed implicit_cast<>. See comment below. (Beman Dawes)
Chris@16 30 // 27 Jun 00 More MSVC6 workarounds
Chris@16 31 // 15 Jun 00 Add workarounds for MSVC6
Chris@16 32 // 2 Feb 00 Remove bad_numeric_cast ";" syntax error (Doncho Angelov)
Chris@16 33 // 26 Jan 00 Add missing throw() to bad_numeric_cast::what(0 (Adam Levar)
Chris@16 34 // 29 Dec 99 Change using declarations so usages in other namespaces work
Chris@16 35 // correctly (Dave Abrahams)
Chris@16 36 // 23 Sep 99 Change polymorphic_downcast assert to also detect M.I. errors
Chris@16 37 // as suggested Darin Adler and improved by Valentin Bonnard.
Chris@16 38 // 2 Sep 99 Remove controversial asserts, simplify, rename.
Chris@16 39 // 30 Aug 99 Move to cast.hpp, replace value_cast with numeric_cast,
Chris@16 40 // place in nested namespace.
Chris@16 41 // 3 Aug 99 Initial version
Chris@16 42
Chris@16 43 #ifndef BOOST_CAST_HPP
Chris@16 44 #define BOOST_CAST_HPP
Chris@16 45
Chris@16 46 # include <boost/config.hpp>
Chris@16 47 # include <boost/assert.hpp>
Chris@16 48 # include <typeinfo>
Chris@16 49 # include <boost/type.hpp>
Chris@16 50 # include <boost/limits.hpp>
Chris@16 51 # include <boost/detail/select_type.hpp>
Chris@16 52
Chris@16 53 // It has been demonstrated numerous times that MSVC 6.0 fails silently at link
Chris@16 54 // time if you use a template function which has template parameters that don't
Chris@16 55 // appear in the function's argument list.
Chris@16 56 //
Chris@16 57 // TODO: Add this to config.hpp?
Chris@16 58 # if defined(BOOST_MSVC) && BOOST_MSVC < 1300
Chris@16 59 # define BOOST_EXPLICIT_DEFAULT_TARGET , ::boost::type<Target>* = 0
Chris@16 60 # else
Chris@16 61 # define BOOST_EXPLICIT_DEFAULT_TARGET
Chris@16 62 # endif
Chris@16 63
Chris@16 64 namespace boost
Chris@16 65 {
Chris@16 66 // See the documentation for descriptions of how to choose between
Chris@16 67 // static_cast<>, dynamic_cast<>, polymorphic_cast<> and polymorphic_downcast<>
Chris@16 68
Chris@16 69 // polymorphic_cast --------------------------------------------------------//
Chris@16 70
Chris@16 71 // Runtime checked polymorphic downcasts and crosscasts.
Chris@16 72 // Suggested in The C++ Programming Language, 3rd Ed, Bjarne Stroustrup,
Chris@16 73 // section 15.8 exercise 1, page 425.
Chris@16 74
Chris@16 75 template <class Target, class Source>
Chris@16 76 inline Target polymorphic_cast(Source* x BOOST_EXPLICIT_DEFAULT_TARGET)
Chris@16 77 {
Chris@16 78 Target tmp = dynamic_cast<Target>(x);
Chris@16 79 if ( tmp == 0 ) throw std::bad_cast();
Chris@16 80 return tmp;
Chris@16 81 }
Chris@16 82
Chris@16 83 // polymorphic_downcast ----------------------------------------------------//
Chris@16 84
Chris@16 85 // BOOST_ASSERT() checked polymorphic downcast. Crosscasts prohibited.
Chris@16 86
Chris@16 87 // WARNING: Because this cast uses BOOST_ASSERT(), it violates
Chris@16 88 // the One Definition Rule if used in multiple translation units
Chris@16 89 // where BOOST_DISABLE_ASSERTS, BOOST_ENABLE_ASSERT_HANDLER
Chris@16 90 // NDEBUG are defined inconsistently.
Chris@16 91
Chris@16 92 // Contributed by Dave Abrahams
Chris@16 93
Chris@16 94 template <class Target, class Source>
Chris@16 95 inline Target polymorphic_downcast(Source* x BOOST_EXPLICIT_DEFAULT_TARGET)
Chris@16 96 {
Chris@16 97 BOOST_ASSERT( dynamic_cast<Target>(x) == x ); // detect logic error
Chris@16 98 return static_cast<Target>(x);
Chris@16 99 }
Chris@16 100
Chris@16 101 # undef BOOST_EXPLICIT_DEFAULT_TARGET
Chris@16 102
Chris@16 103 } // namespace boost
Chris@16 104
Chris@16 105 # include <boost/numeric/conversion/cast.hpp>
Chris@16 106
Chris@16 107 #endif // BOOST_CAST_HPP