annotate DEPENDENCIES/generic/include/boost/polymorphic_cast.hpp @ 125:34e428693f5d vext

Vext -> Repoint
author Chris Cannam
date Thu, 14 Jun 2018 11:15:39 +0100
parents f46d142149f5
children
rev   line source
Chris@102 1 // boost polymorphic_cast.hpp header file ----------------------------------------------//
Chris@102 2
Chris@102 3 // (C) Copyright Kevlin Henney and Dave Abrahams 1999.
Chris@102 4 // (C) Copyright Boris Rasin 2014.
Chris@102 5 // Distributed under the Boost
Chris@102 6 // Software License, Version 1.0. (See accompanying file
Chris@102 7 // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
Chris@102 8
Chris@102 9 // See http://www.boost.org/libs/conversion for Documentation.
Chris@102 10
Chris@102 11 // Revision History
Chris@102 12 // 10 Nov 14 polymorphic_pointer_downcast moved to a separate header,
Chris@102 13 // minor improvements to stisfy latest Boost coding style
Chris@102 14 // 08 Nov 14 Add polymorphic_pointer_downcast (Boris Rasin)
Chris@102 15 // 09 Jun 14 "cast.hpp" was renamed to "polymorphic_cast.hpp" and
Chris@102 16 // inclusion of numeric_cast was removed (Antony Polukhin)
Chris@102 17 // 23 Jun 05 numeric_cast removed and redirected to the new verion (Fernando Cacciola)
Chris@102 18 // 02 Apr 01 Removed BOOST_NO_LIMITS workarounds and included
Chris@102 19 // <boost/limits.hpp> instead (the workaround did not
Chris@102 20 // actually compile when BOOST_NO_LIMITS was defined in
Chris@102 21 // any case, so we loose nothing). (John Maddock)
Chris@102 22 // 21 Jan 01 Undid a bug I introduced yesterday. numeric_cast<> never
Chris@102 23 // worked with stock GCC; trying to get it to do that broke
Chris@102 24 // vc-stlport.
Chris@102 25 // 20 Jan 01 Moved BOOST_NO_LIMITS_COMPILE_TIME_CONSTANTS to config.hpp.
Chris@102 26 // Removed unused BOOST_EXPLICIT_TARGET macro. Moved
Chris@102 27 // boost::detail::type to boost/type.hpp. Made it compile with
Chris@102 28 // stock gcc again (Dave Abrahams)
Chris@102 29 // 29 Nov 00 Remove nested namespace cast, cleanup spacing before Formal
Chris@102 30 // Review (Beman Dawes)
Chris@102 31 // 19 Oct 00 Fix numeric_cast for floating-point types (Dave Abrahams)
Chris@102 32 // 15 Jul 00 Suppress numeric_cast warnings for GCC, Borland and MSVC
Chris@102 33 // (Dave Abrahams)
Chris@102 34 // 30 Jun 00 More MSVC6 wordarounds. See comments below. (Dave Abrahams)
Chris@102 35 // 28 Jun 00 Removed implicit_cast<>. See comment below. (Beman Dawes)
Chris@102 36 // 27 Jun 00 More MSVC6 workarounds
Chris@102 37 // 15 Jun 00 Add workarounds for MSVC6
Chris@102 38 // 2 Feb 00 Remove bad_numeric_cast ";" syntax error (Doncho Angelov)
Chris@102 39 // 26 Jan 00 Add missing throw() to bad_numeric_cast::what(0 (Adam Levar)
Chris@102 40 // 29 Dec 99 Change using declarations so usages in other namespaces work
Chris@102 41 // correctly (Dave Abrahams)
Chris@102 42 // 23 Sep 99 Change polymorphic_downcast assert to also detect M.I. errors
Chris@102 43 // as suggested Darin Adler and improved by Valentin Bonnard.
Chris@102 44 // 2 Sep 99 Remove controversial asserts, simplify, rename.
Chris@102 45 // 30 Aug 99 Move to cast.hpp, replace value_cast with numeric_cast,
Chris@102 46 // place in nested namespace.
Chris@102 47 // 3 Aug 99 Initial version
Chris@102 48
Chris@102 49 #ifndef BOOST_POLYMORPHIC_CAST_HPP
Chris@102 50 #define BOOST_POLYMORPHIC_CAST_HPP
Chris@102 51
Chris@102 52 # include <boost/config.hpp>
Chris@102 53 # include <boost/assert.hpp>
Chris@102 54 # include <boost/throw_exception.hpp>
Chris@102 55 # include <typeinfo>
Chris@102 56
Chris@102 57 #ifdef BOOST_HAS_PRAGMA_ONCE
Chris@102 58 # pragma once
Chris@102 59 #endif
Chris@102 60
Chris@102 61 namespace boost
Chris@102 62 {
Chris@102 63 // See the documentation for descriptions of how to choose between
Chris@102 64 // static_cast<>, dynamic_cast<>, polymorphic_cast<> and polymorphic_downcast<>
Chris@102 65
Chris@102 66 // polymorphic_cast --------------------------------------------------------//
Chris@102 67
Chris@102 68 // Runtime checked polymorphic downcasts and crosscasts.
Chris@102 69 // Suggested in The C++ Programming Language, 3rd Ed, Bjarne Stroustrup,
Chris@102 70 // section 15.8 exercise 1, page 425.
Chris@102 71
Chris@102 72 template <class Target, class Source>
Chris@102 73 inline Target polymorphic_cast(Source* x)
Chris@102 74 {
Chris@102 75 Target tmp = dynamic_cast<Target>(x);
Chris@102 76 if ( tmp == 0 ) boost::throw_exception( std::bad_cast() );
Chris@102 77 return tmp;
Chris@102 78 }
Chris@102 79
Chris@102 80 // polymorphic_downcast ----------------------------------------------------//
Chris@102 81
Chris@102 82 // BOOST_ASSERT() checked polymorphic downcast. Crosscasts prohibited.
Chris@102 83
Chris@102 84 // WARNING: Because this cast uses BOOST_ASSERT(), it violates
Chris@102 85 // the One Definition Rule if used in multiple translation units
Chris@102 86 // where BOOST_DISABLE_ASSERTS, BOOST_ENABLE_ASSERT_HANDLER
Chris@102 87 // NDEBUG are defined inconsistently.
Chris@102 88
Chris@102 89 // Contributed by Dave Abrahams
Chris@102 90
Chris@102 91 template <class Target, class Source>
Chris@102 92 inline Target polymorphic_downcast(Source* x)
Chris@102 93 {
Chris@102 94 BOOST_ASSERT( dynamic_cast<Target>(x) == x ); // detect logic error
Chris@102 95 return static_cast<Target>(x);
Chris@102 96 }
Chris@102 97
Chris@102 98 } // namespace boost
Chris@102 99
Chris@102 100 #endif // BOOST_POLYMORPHIC_CAST_HPP