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boost-1.40
...
boost-1.44
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ca7db1f361 | |||
2a7e81e07f | |||
13da21e7b1 | |||
b3ffef536d | |||
e2c98762db | |||
8af4250c3c | |||
e30889304c | |||
b4dee80e61 | |||
a47dce770c | |||
dab1e8e522 | |||
583422cda2 | |||
ee146a02a1 | |||
c131cbd0b2 | |||
f8bef7ba95 | |||
e54cbf3053 |
@ -1,37 +0,0 @@
|
||||
#
|
||||
# Copyright Troy D. Straszheim
|
||||
#
|
||||
# Distributed under the Boost Software License, Version 1.0.
|
||||
# See http://www.boost.org/LICENSE_1_0.txt
|
||||
#
|
||||
#----------------------------------------------------------------------------
|
||||
# This file was automatically generated from the original CMakeLists.txt file
|
||||
# Add a variable to hold the headers for the library
|
||||
set (lib_headers
|
||||
assert.hpp
|
||||
call_traits.hpp
|
||||
checked_delete.hpp
|
||||
compressed_pair.hpp
|
||||
current_function.hpp
|
||||
operators.hpp
|
||||
throw_exception.hpp
|
||||
utility.hpp
|
||||
utility
|
||||
)
|
||||
|
||||
# Add a library target to the build system
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||||
boost_library_project(
|
||||
utility
|
||||
# SRCDIRS
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||||
TESTDIRS test swap/test enable_if/test
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HEADERS ${lib_headers}
|
||||
# DOCDIRS
|
||||
DESCRIPTION "Various small utilities for C++ programming."
|
||||
MODULARIZED
|
||||
AUTHORS "David Abrahams <dave -at- boostpro.com>"
|
||||
"Brad King"
|
||||
"Douglas Gregor <doug.gregor -at- gmail.com>"
|
||||
# MAINTAINERS
|
||||
)
|
||||
|
||||
|
@ -281,7 +281,7 @@ object_id_compare::operator ()
|
||||
}
|
||||
else
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||||
{
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||||
return a.second->before( *b.second );
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return a.second->before( *b.second ) != 0;
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||||
}
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||||
}
|
||||
}
|
||||
|
@ -11,6 +11,10 @@
|
||||
#include <algorithm>
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||||
#include <cstddef>
|
||||
|
||||
#ifdef BOOST_MSVC
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||||
#pragma warning(disable:4996) // warning C4996: 'std::equal': Function call with parameters that may be unsafe - this call relies on the caller to check that the passed values are correct. To disable this warning, use -D_SCL_SECURE_NO_WARNINGS. See documentation on how to use Visual C++ 'Checked Iterators'
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||||
#endif
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||||
|
||||
/*
|
||||
Note: This file tests every single valid bit-grouping on its own, and some
|
||||
random combinations of bit-groupings.
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||||
|
@ -21,6 +21,10 @@
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||||
#include <libs/type_traits/test/test.hpp>
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||||
#include <libs/type_traits/test/check_type.hpp>
|
||||
|
||||
#ifdef BOOST_MSVC
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||||
#pragma warning(disable:4181) // : warning C4181: qualifier applied to reference type; ignored
|
||||
#endif
|
||||
|
||||
// a way prevent warnings for unused variables
|
||||
template<class T> inline void unused_variable(const T&) {}
|
||||
|
||||
@ -52,7 +56,8 @@ struct contained
|
||||
const_reference const_get()const { return v_; }
|
||||
// pass value:
|
||||
void call(param_type){}
|
||||
|
||||
private:
|
||||
contained& operator=(const contained&);
|
||||
};
|
||||
|
||||
#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
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||||
@ -77,6 +82,8 @@ struct contained<T[N]>
|
||||
reference get() { return v_; }
|
||||
const_reference const_get()const { return v_; }
|
||||
void call(param_type){}
|
||||
private:
|
||||
contained& operator=(const contained&);
|
||||
};
|
||||
#endif
|
||||
|
||||
@ -197,7 +204,7 @@ struct comparible_UDT
|
||||
bool operator == (const comparible_UDT& v){ return v.i_ == i_; }
|
||||
};
|
||||
|
||||
int main(int argc, char *argv[ ])
|
||||
int main()
|
||||
{
|
||||
call_traits_checker<comparible_UDT> c1;
|
||||
comparible_UDT u;
|
||||
|
@ -1,20 +0,0 @@
|
||||
#
|
||||
# Copyright Troy D. Straszheim
|
||||
#
|
||||
# Distributed under the Boost Software License, Version 1.0.
|
||||
# See http://www.boost.org/LICENSE_1_0.txt
|
||||
#
|
||||
foreach(T
|
||||
constructors
|
||||
dummy_arg_disambiguation
|
||||
lazy
|
||||
lazy_test
|
||||
member_templates
|
||||
namespace_disambiguation
|
||||
no_disambiguation
|
||||
partial_specializations
|
||||
)
|
||||
boost_test_run(${T} DEPENDS boost_test_exec_monitor)
|
||||
endforeach()
|
||||
|
||||
|
@ -6,8 +6,6 @@
|
||||
#ifndef UUID_1D94A7C6054E11DB9804B622A1EF5492
|
||||
#define UUID_1D94A7C6054E11DB9804B622A1EF5492
|
||||
|
||||
//The header <boost/exception.hpp> has been deprecated.
|
||||
//Please #include <boost/exception/all.hpp> instead.
|
||||
#include <boost/exception/all.hpp>
|
||||
#error The header <boost/exception.hpp> has been deprecated. Please #include <boost/exception/all.hpp> instead.
|
||||
|
||||
#endif
|
||||
|
@ -4,7 +4,7 @@
|
||||
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
|
||||
// http://www.boost.org/LICENSE_1_0.txt)
|
||||
//
|
||||
// See http://www.boost.org/lib/optional for documentation.
|
||||
// See http://www.boost.org/libs/optional for documentation.
|
||||
//
|
||||
// You are welcome to contact the author at:
|
||||
// fernando_cacciola@hotmail.com
|
||||
|
@ -5,7 +5,7 @@
|
||||
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
|
||||
// http://www.boost.org/LICENSE_1_0.txt)
|
||||
//
|
||||
// See http://www.boost.org/lib/optional for documentation.
|
||||
// See http://www.boost.org/libs/optional for documentation.
|
||||
//
|
||||
// You are welcome to contact the author at:
|
||||
// fernando_cacciola@hotmail.com
|
||||
|
@ -5,7 +5,7 @@
|
||||
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
|
||||
// http://www.boost.org/LICENSE_1_0.txt)
|
||||
//
|
||||
// See http://www.boost.org/lib/optional for documentation.
|
||||
// See http://www.boost.org/libs/optional for documentation.
|
||||
//
|
||||
// You are welcome to contact the author at:
|
||||
// fernando_cacciola@hotmail.com
|
||||
|
@ -20,10 +20,69 @@
|
||||
#if !BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x551))
|
||||
template<typename F BOOST_PP_COMMA_IF(BOOST_PP_ITERATION())
|
||||
BOOST_PP_ENUM_PARAMS(BOOST_PP_ITERATION(),typename T)>
|
||||
struct result_of<F(BOOST_RESULT_OF_ARGS)>
|
||||
: boost::detail::result_of_impl<F, F(BOOST_RESULT_OF_ARGS), (boost::detail::has_result_type<F>::value)> {};
|
||||
struct tr1_result_of<F(BOOST_RESULT_OF_ARGS)>
|
||||
: mpl::if_<
|
||||
mpl::or_< is_pointer<F>, is_member_function_pointer<F> >
|
||||
, boost::detail::tr1_result_of_impl<
|
||||
typename remove_cv<F>::type,
|
||||
typename remove_cv<F>::type(BOOST_RESULT_OF_ARGS),
|
||||
(boost::detail::has_result_type<F>::value)>
|
||||
, boost::detail::tr1_result_of_impl<
|
||||
F,
|
||||
F(BOOST_RESULT_OF_ARGS),
|
||||
(boost::detail::has_result_type<F>::value)> >::type { };
|
||||
#endif
|
||||
|
||||
#if !defined(BOOST_NO_DECLTYPE) && defined(BOOST_RESULT_OF_USE_DECLTYPE)
|
||||
|
||||
// As of N2588, C++0x result_of only supports function call
|
||||
// expressions of the form f(x). This precludes support for member
|
||||
// function pointers, which are invoked with expressions of the form
|
||||
// o->*f(x). This implementation supports both.
|
||||
template<typename F BOOST_PP_COMMA_IF(BOOST_PP_ITERATION())
|
||||
BOOST_PP_ENUM_PARAMS(BOOST_PP_ITERATION(),typename T)>
|
||||
struct result_of<F(BOOST_PP_ENUM_PARAMS(BOOST_PP_ITERATION(),T))>
|
||||
: mpl::if_<
|
||||
mpl::or_< is_pointer<F>, is_member_function_pointer<F> >
|
||||
, detail::tr1_result_of_impl<
|
||||
typename remove_cv<F>::type,
|
||||
typename remove_cv<F>::type(BOOST_PP_ENUM_PARAMS(BOOST_PP_ITERATION(),T)), false
|
||||
>
|
||||
, detail::cpp0x_result_of_impl<
|
||||
F(BOOST_PP_ENUM_PARAMS(BOOST_PP_ITERATION(),T))
|
||||
>
|
||||
>::type
|
||||
{};
|
||||
|
||||
namespace detail {
|
||||
|
||||
# define BOOST_RESULT_OF_STATIC_MEMBERS(z, n, _) \
|
||||
static T ## n t ## n; \
|
||||
/**/
|
||||
|
||||
template<typename F BOOST_PP_COMMA_IF(BOOST_PP_ITERATION())
|
||||
BOOST_PP_ENUM_PARAMS(BOOST_PP_ITERATION(),typename T)>
|
||||
class cpp0x_result_of_impl<F(BOOST_PP_ENUM_PARAMS(BOOST_PP_ITERATION(),T))>
|
||||
{
|
||||
static F f;
|
||||
BOOST_PP_REPEAT(BOOST_PP_ITERATION(), BOOST_RESULT_OF_STATIC_MEMBERS, _)
|
||||
public:
|
||||
typedef decltype(f(BOOST_PP_ENUM_PARAMS(BOOST_PP_ITERATION(),t))) type;
|
||||
};
|
||||
|
||||
} // namespace detail
|
||||
|
||||
#else // defined(BOOST_NO_DECLTYPE)
|
||||
|
||||
#if !BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x551))
|
||||
template<typename F BOOST_PP_COMMA_IF(BOOST_PP_ITERATION())
|
||||
BOOST_PP_ENUM_PARAMS(BOOST_PP_ITERATION(),typename T)>
|
||||
struct result_of<F(BOOST_RESULT_OF_ARGS)>
|
||||
: tr1_result_of<F(BOOST_RESULT_OF_ARGS)> { };
|
||||
#endif
|
||||
|
||||
#endif // defined(BOOST_NO_DECLTYPE)
|
||||
|
||||
#undef BOOST_RESULT_OF_ARGS
|
||||
|
||||
#if BOOST_PP_ITERATION() >= 1
|
||||
@ -32,14 +91,14 @@ namespace detail {
|
||||
|
||||
template<typename R, typename FArgs BOOST_PP_COMMA_IF(BOOST_PP_ITERATION())
|
||||
BOOST_PP_ENUM_PARAMS(BOOST_PP_ITERATION(),typename T)>
|
||||
struct result_of_impl<R (*)(BOOST_PP_ENUM_PARAMS(BOOST_PP_ITERATION(),T)), FArgs, false>
|
||||
struct tr1_result_of_impl<R (*)(BOOST_PP_ENUM_PARAMS(BOOST_PP_ITERATION(),T)), FArgs, false>
|
||||
{
|
||||
typedef R type;
|
||||
};
|
||||
|
||||
template<typename R, typename FArgs BOOST_PP_COMMA_IF(BOOST_PP_ITERATION())
|
||||
BOOST_PP_ENUM_PARAMS(BOOST_PP_ITERATION(),typename T)>
|
||||
struct result_of_impl<R (&)(BOOST_PP_ENUM_PARAMS(BOOST_PP_ITERATION(),T)), FArgs, false>
|
||||
struct tr1_result_of_impl<R (&)(BOOST_PP_ENUM_PARAMS(BOOST_PP_ITERATION(),T)), FArgs, false>
|
||||
{
|
||||
typedef R type;
|
||||
};
|
||||
@ -47,7 +106,7 @@ struct result_of_impl<R (&)(BOOST_PP_ENUM_PARAMS(BOOST_PP_ITERATION(),T)), FArgs
|
||||
#if !BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x551))
|
||||
template<typename R, typename FArgs BOOST_PP_COMMA_IF(BOOST_PP_ITERATION())
|
||||
BOOST_PP_ENUM_PARAMS(BOOST_PP_ITERATION(),typename T)>
|
||||
struct result_of_impl<R (T0::*)
|
||||
struct tr1_result_of_impl<R (T0::*)
|
||||
(BOOST_PP_ENUM_SHIFTED_PARAMS(BOOST_PP_ITERATION(),T)),
|
||||
FArgs, false>
|
||||
{
|
||||
@ -56,7 +115,7 @@ struct result_of_impl<R (T0::*)
|
||||
|
||||
template<typename R, typename FArgs BOOST_PP_COMMA_IF(BOOST_PP_ITERATION())
|
||||
BOOST_PP_ENUM_PARAMS(BOOST_PP_ITERATION(),typename T)>
|
||||
struct result_of_impl<R (T0::*)
|
||||
struct tr1_result_of_impl<R (T0::*)
|
||||
(BOOST_PP_ENUM_SHIFTED_PARAMS(BOOST_PP_ITERATION(),T))
|
||||
const,
|
||||
FArgs, false>
|
||||
@ -66,7 +125,7 @@ struct result_of_impl<R (T0::*)
|
||||
|
||||
template<typename R, typename FArgs BOOST_PP_COMMA_IF(BOOST_PP_ITERATION())
|
||||
BOOST_PP_ENUM_PARAMS(BOOST_PP_ITERATION(),typename T)>
|
||||
struct result_of_impl<R (T0::*)
|
||||
struct tr1_result_of_impl<R (T0::*)
|
||||
(BOOST_PP_ENUM_SHIFTED_PARAMS(BOOST_PP_ITERATION(),T))
|
||||
volatile,
|
||||
FArgs, false>
|
||||
@ -76,7 +135,7 @@ struct result_of_impl<R (T0::*)
|
||||
|
||||
template<typename R, typename FArgs BOOST_PP_COMMA_IF(BOOST_PP_ITERATION())
|
||||
BOOST_PP_ENUM_PARAMS(BOOST_PP_ITERATION(),typename T)>
|
||||
struct result_of_impl<R (T0::*)
|
||||
struct tr1_result_of_impl<R (T0::*)
|
||||
(BOOST_PP_ENUM_SHIFTED_PARAMS(BOOST_PP_ITERATION(),T))
|
||||
const volatile,
|
||||
FArgs, false>
|
||||
|
@ -5,7 +5,7 @@
|
||||
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
|
||||
// http://www.boost.org/LICENSE_1_0.txt)
|
||||
//
|
||||
// See http://www.boost.org/lib/optional for documentation.
|
||||
// See http://www.boost.org/libs/optional for documentation.
|
||||
//
|
||||
// You are welcome to contact the author at:
|
||||
// fernando_cacciola@hotmail.com
|
||||
|
@ -10,13 +10,18 @@
|
||||
#define BOOST_RESULT_OF_HPP
|
||||
|
||||
#include <boost/config.hpp>
|
||||
#include <boost/type_traits/ice.hpp>
|
||||
#include <boost/type.hpp>
|
||||
#include <boost/preprocessor.hpp>
|
||||
#include <boost/preprocessor/iteration/iterate.hpp>
|
||||
#include <boost/preprocessor/punctuation/comma_if.hpp>
|
||||
#include <boost/preprocessor/repetition/enum_params.hpp>
|
||||
#include <boost/preprocessor/repetition/enum_shifted_params.hpp>
|
||||
#include <boost/detail/workaround.hpp>
|
||||
#include <boost/mpl/has_xxx.hpp>
|
||||
#include <boost/mpl/if.hpp>
|
||||
#include <boost/mpl/bool.hpp>
|
||||
#include <boost/mpl/or.hpp>
|
||||
#include <boost/type_traits/is_pointer.hpp>
|
||||
#include <boost/type_traits/is_member_function_pointer.hpp>
|
||||
#include <boost/type_traits/remove_cv.hpp>
|
||||
|
||||
#ifndef BOOST_RESULT_OF_NUM_ARGS
|
||||
# define BOOST_RESULT_OF_NUM_ARGS 10
|
||||
@ -25,13 +30,15 @@
|
||||
namespace boost {
|
||||
|
||||
template<typename F> struct result_of;
|
||||
template<typename F> struct tr1_result_of; // a TR1-style implementation of result_of
|
||||
|
||||
#if !defined(BOOST_NO_SFINAE) && !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
|
||||
namespace detail {
|
||||
|
||||
BOOST_MPL_HAS_XXX_TRAIT_DEF(result_type)
|
||||
|
||||
template<typename F, typename FArgs, bool HasResultType> struct result_of_impl;
|
||||
template<typename F, typename FArgs, bool HasResultType> struct tr1_result_of_impl;
|
||||
template<typename F> struct cpp0x_result_of_impl;
|
||||
|
||||
template<typename F>
|
||||
struct result_of_void_impl
|
||||
@ -51,8 +58,13 @@ struct result_of_void_impl<R (&)(void)>
|
||||
typedef R type;
|
||||
};
|
||||
|
||||
// Determine the return type of a function pointer or pointer to member.
|
||||
template<typename F, typename FArgs>
|
||||
struct result_of_impl<F, FArgs, true>
|
||||
struct result_of_pointer
|
||||
: tr1_result_of_impl<typename remove_cv<F>::type, FArgs, false> { };
|
||||
|
||||
template<typename F, typename FArgs>
|
||||
struct tr1_result_of_impl<F, FArgs, true>
|
||||
{
|
||||
typedef typename F::result_type type;
|
||||
};
|
||||
@ -68,7 +80,7 @@ struct result_of_nested_result : F::template result<FArgs>
|
||||
{};
|
||||
|
||||
template<typename F, typename FArgs>
|
||||
struct result_of_impl<F, FArgs, false>
|
||||
struct tr1_result_of_impl<F, FArgs, false>
|
||||
: mpl::if_<is_function_with_no_args<FArgs>,
|
||||
result_of_void_impl<F>,
|
||||
result_of_nested_result<F, FArgs> >::type
|
||||
|
@ -5,7 +5,7 @@
|
||||
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
|
||||
// http://www.boost.org/LICENSE_1_0.txt)
|
||||
//
|
||||
// See http://www.boost.org/lib/optional for documentation.
|
||||
// See http://www.boost.org/libs/optional for documentation.
|
||||
//
|
||||
// You are welcome to contact the author at:
|
||||
// fernando_cacciola@hotmail.com
|
||||
|
@ -8,6 +8,9 @@
|
||||
// 24 Dec 2007 (Refactored and worked around various compiler bugs) Fernando Cacciola, Niels Dekker
|
||||
// 23 May 2008 (Fixed operator= const issue, added initialized_value) Niels Dekker, Fernando Cacciola
|
||||
// 21 Ago 2008 (Added swap) Niels Dekker, Fernando Cacciola
|
||||
// 20 Feb 2009 (Fixed logical const-ness issues) Niels Dekker, Fernando Cacciola
|
||||
// 03 Apr 2010 (Added initialized<T>, suggested by Jeffrey Hellrung, fixing #3472) Niels Dekker
|
||||
// 30 May 2010 (Made memset call conditional, fixing #3869) Niels Dekker
|
||||
//
|
||||
#ifndef BOOST_UTILITY_VALUE_INIT_21AGO2002_HPP
|
||||
#define BOOST_UTILITY_VALUE_INIT_21AGO2002_HPP
|
||||
@ -19,6 +22,7 @@
|
||||
// contains. More details on these issues are at libs/utility/value_init.htm
|
||||
|
||||
#include <boost/aligned_storage.hpp>
|
||||
#include <boost/config.hpp> // For BOOST_NO_COMPLETE_VALUE_INITIALIZATION.
|
||||
#include <boost/detail/workaround.hpp>
|
||||
#include <boost/static_assert.hpp>
|
||||
#include <boost/type_traits/cv_traits.hpp>
|
||||
@ -27,10 +31,39 @@
|
||||
#include <cstring>
|
||||
#include <new>
|
||||
|
||||
#ifdef BOOST_MSVC
|
||||
#pragma warning(push)
|
||||
#if _MSC_VER >= 1310
|
||||
// It is safe to ignore the following warning from MSVC 7.1 or higher:
|
||||
// "warning C4351: new behavior: elements of array will be default initialized"
|
||||
#pragma warning(disable: 4351)
|
||||
// It is safe to ignore the following MSVC warning, which may pop up when T is
|
||||
// a const type: "warning C4512: assignment operator could not be generated".
|
||||
#pragma warning(disable: 4512)
|
||||
#endif
|
||||
#endif
|
||||
|
||||
#ifdef BOOST_NO_COMPLETE_VALUE_INITIALIZATION
|
||||
// Implementation detail: The macro BOOST_DETAIL_VALUE_INIT_WORKAROUND_SUGGESTED
|
||||
// suggests that a workaround should be applied, because of compiler issues
|
||||
// regarding value-initialization.
|
||||
#define BOOST_DETAIL_VALUE_INIT_WORKAROUND_SUGGESTED
|
||||
#endif
|
||||
|
||||
// Implementation detail: The macro BOOST_DETAIL_VALUE_INIT_WORKAROUND
|
||||
// switches the value-initialization workaround either on or off.
|
||||
#ifndef BOOST_DETAIL_VALUE_INIT_WORKAROUND
|
||||
#ifdef BOOST_DETAIL_VALUE_INIT_WORKAROUND_SUGGESTED
|
||||
#define BOOST_DETAIL_VALUE_INIT_WORKAROUND 1
|
||||
#else
|
||||
#define BOOST_DETAIL_VALUE_INIT_WORKAROUND 0
|
||||
#endif
|
||||
#endif
|
||||
|
||||
namespace boost {
|
||||
|
||||
template<class T>
|
||||
class value_initialized
|
||||
class initialized
|
||||
{
|
||||
private :
|
||||
struct wrapper
|
||||
@ -39,6 +72,18 @@ class value_initialized
|
||||
typename
|
||||
#endif
|
||||
remove_const<T>::type data;
|
||||
|
||||
wrapper()
|
||||
:
|
||||
data()
|
||||
{
|
||||
}
|
||||
|
||||
wrapper(T const & arg)
|
||||
:
|
||||
data(arg)
|
||||
{
|
||||
}
|
||||
};
|
||||
|
||||
mutable
|
||||
@ -54,30 +99,25 @@ class value_initialized
|
||||
|
||||
public :
|
||||
|
||||
value_initialized()
|
||||
initialized()
|
||||
{
|
||||
#if BOOST_DETAIL_VALUE_INIT_WORKAROUND
|
||||
std::memset(&x, 0, sizeof(x));
|
||||
#ifdef BOOST_MSVC
|
||||
#pragma warning(push)
|
||||
#if _MSC_VER >= 1310
|
||||
// When using MSVC 7.1 or higher, the following placement new expression may trigger warning C4345:
|
||||
// "behavior change: an object of POD type constructed with an initializer of the form ()
|
||||
// will be default-initialized". It is safe to ignore this warning when using value_initialized.
|
||||
#pragma warning(disable: 4345)
|
||||
#endif
|
||||
#endif
|
||||
new (wrapper_address()) wrapper();
|
||||
#ifdef BOOST_MSVC
|
||||
#pragma warning(pop)
|
||||
#endif
|
||||
}
|
||||
|
||||
value_initialized(value_initialized const & arg)
|
||||
initialized(initialized const & arg)
|
||||
{
|
||||
new (wrapper_address()) wrapper( static_cast<wrapper const &>(*(arg.wrapper_address())));
|
||||
}
|
||||
|
||||
value_initialized & operator=(value_initialized const & arg)
|
||||
explicit initialized(T const & arg)
|
||||
{
|
||||
new (wrapper_address()) wrapper(arg);
|
||||
}
|
||||
|
||||
initialized & operator=(initialized const & arg)
|
||||
{
|
||||
// Assignment is only allowed when T is non-const.
|
||||
BOOST_STATIC_ASSERT( ! is_const<T>::value );
|
||||
@ -85,25 +125,96 @@ class value_initialized
|
||||
return *this;
|
||||
}
|
||||
|
||||
~value_initialized()
|
||||
~initialized()
|
||||
{
|
||||
wrapper_address()->wrapper::~wrapper();
|
||||
}
|
||||
|
||||
T& data() const
|
||||
T const & data() const
|
||||
{
|
||||
return wrapper_address()->data;
|
||||
}
|
||||
|
||||
void swap(value_initialized & arg)
|
||||
T& data()
|
||||
{
|
||||
return wrapper_address()->data;
|
||||
}
|
||||
|
||||
void swap(initialized & arg)
|
||||
{
|
||||
::boost::swap( this->data(), arg.data() );
|
||||
}
|
||||
|
||||
operator T&() const { return this->data(); }
|
||||
operator T const &() const
|
||||
{
|
||||
return wrapper_address()->data;
|
||||
}
|
||||
|
||||
operator T&()
|
||||
{
|
||||
return wrapper_address()->data;
|
||||
}
|
||||
|
||||
} ;
|
||||
|
||||
template<class T>
|
||||
T const& get ( initialized<T> const& x )
|
||||
{
|
||||
return x.data() ;
|
||||
}
|
||||
|
||||
template<class T>
|
||||
T& get ( initialized<T>& x )
|
||||
{
|
||||
return x.data() ;
|
||||
}
|
||||
|
||||
template<class T>
|
||||
void swap ( initialized<T> & lhs, initialized<T> & rhs )
|
||||
{
|
||||
lhs.swap(rhs) ;
|
||||
}
|
||||
|
||||
template<class T>
|
||||
class value_initialized
|
||||
{
|
||||
private :
|
||||
|
||||
// initialized<T> does value-initialization by default.
|
||||
initialized<T> m_data;
|
||||
|
||||
public :
|
||||
|
||||
value_initialized()
|
||||
:
|
||||
m_data()
|
||||
{ }
|
||||
|
||||
T const & data() const
|
||||
{
|
||||
return m_data.data();
|
||||
}
|
||||
|
||||
T& data()
|
||||
{
|
||||
return m_data.data();
|
||||
}
|
||||
|
||||
void swap(value_initialized & arg)
|
||||
{
|
||||
m_data.swap(arg.m_data);
|
||||
}
|
||||
|
||||
operator T const &() const
|
||||
{
|
||||
return m_data;
|
||||
}
|
||||
|
||||
operator T&()
|
||||
{
|
||||
return m_data;
|
||||
}
|
||||
} ;
|
||||
|
||||
|
||||
template<class T>
|
||||
@ -111,6 +222,7 @@ T const& get ( value_initialized<T> const& x )
|
||||
{
|
||||
return x.data() ;
|
||||
}
|
||||
|
||||
template<class T>
|
||||
T& get ( value_initialized<T>& x )
|
||||
{
|
||||
@ -130,7 +242,7 @@ class initialized_value_t
|
||||
|
||||
template <class T> operator T() const
|
||||
{
|
||||
return get( value_initialized<T>() );
|
||||
return initialized<T>().data();
|
||||
}
|
||||
};
|
||||
|
||||
@ -139,5 +251,8 @@ initialized_value_t const initialized_value = {} ;
|
||||
|
||||
} // namespace boost
|
||||
|
||||
#ifdef BOOST_MSVC
|
||||
#pragma warning(pop)
|
||||
#endif
|
||||
|
||||
#endif
|
||||
|
@ -24,6 +24,7 @@
|
||||
<a href="iterator_adaptors.htm">iterator_adaptors</a><br>
|
||||
<a href="generator_iterator.htm">generator iterator adaptors</a><br>
|
||||
<a href="operators.htm">operators</a><br>
|
||||
<a href="swap.html">swap</a><br>
|
||||
<a href="throw_exception.html">throw_exception</a><br>
|
||||
<a href="utility.htm">utility</a><br>
|
||||
<a href="value_init.htm">value_init</a></p>
|
||||
|
116
initialized_test.cpp
Normal file
116
initialized_test.cpp
Normal file
@ -0,0 +1,116 @@
|
||||
// Copyright 2010, Niels Dekker.
|
||||
//
|
||||
// Distributed under the Boost Software License, Version 1.0. (See
|
||||
// accompanying file LICENSE_1_0.txt or copy at
|
||||
// http://www.boost.org/LICENSE_1_0.txt)
|
||||
//
|
||||
// Test program for boost::initialized<T>.
|
||||
//
|
||||
// 2 May 2010 (Created) Niels Dekker
|
||||
|
||||
#include <boost/utility/value_init.hpp>
|
||||
#include <boost/detail/lightweight_test.hpp>
|
||||
|
||||
#include <string>
|
||||
|
||||
namespace
|
||||
{
|
||||
// Typical use case for boost::initialized<T>: A generic class that
|
||||
// holds a value of type T, which must be initialized by either
|
||||
// value-initialization or direct-initialization.
|
||||
template <class T> class key_value_pair
|
||||
{
|
||||
std::string m_key;
|
||||
boost::initialized<T> m_value;
|
||||
public:
|
||||
|
||||
// Value-initializes the object held by m_value.
|
||||
key_value_pair() { }
|
||||
|
||||
// Value-initializes the object held by m_value.
|
||||
explicit key_value_pair(const std::string& key)
|
||||
:
|
||||
m_key(key)
|
||||
{
|
||||
}
|
||||
|
||||
// Direct-initializes the object held by m_value.
|
||||
key_value_pair(const std::string& key, const T& value)
|
||||
:
|
||||
m_key(key), m_value(value)
|
||||
{
|
||||
}
|
||||
|
||||
const T& get_value() const
|
||||
{
|
||||
return m_value;
|
||||
}
|
||||
};
|
||||
|
||||
|
||||
// Tells whether the argument is value-initialized.
|
||||
bool is_value_initialized(const int& arg)
|
||||
{
|
||||
return arg == 0;
|
||||
}
|
||||
|
||||
|
||||
// Tells whether the argument is value-initialized.
|
||||
bool is_value_initialized(const std::string& arg)
|
||||
{
|
||||
return arg.empty();
|
||||
}
|
||||
|
||||
struct foo
|
||||
{
|
||||
int data;
|
||||
};
|
||||
|
||||
bool operator==(const foo& lhs, const foo& rhs)
|
||||
{
|
||||
return lhs.data == rhs.data;
|
||||
}
|
||||
|
||||
|
||||
// Tells whether the argument is value-initialized.
|
||||
bool is_value_initialized(const foo& arg)
|
||||
{
|
||||
return arg.data == 0;
|
||||
}
|
||||
|
||||
|
||||
template <class T>
|
||||
void test_key_value_pair(const T& magic_value)
|
||||
{
|
||||
// The value component of a default key_value_pair must be value-initialized.
|
||||
key_value_pair<T> default_key_value_pair;
|
||||
BOOST_TEST( is_value_initialized(default_key_value_pair.get_value() ) );
|
||||
|
||||
// The value component of a key_value_pair that only has its key explicitly specified
|
||||
// must also be value-initialized.
|
||||
BOOST_TEST( is_value_initialized(key_value_pair<T>("key").get_value()) );
|
||||
|
||||
// However, the value component of the following key_value_pair must be
|
||||
// "magic_value", as it must be direct-initialized.
|
||||
BOOST_TEST( key_value_pair<T>("key", magic_value).get_value() == magic_value );
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
// Tests boost::initialize for a fundamental type, a type with a
|
||||
// user-defined constructor, and a user-defined type without
|
||||
// a user-defined constructor.
|
||||
int main()
|
||||
{
|
||||
|
||||
const int magic_number = 42;
|
||||
test_key_value_pair(magic_number);
|
||||
|
||||
const std::string magic_string = "magic value";
|
||||
test_key_value_pair(magic_string);
|
||||
|
||||
const foo magic_foo = { 42 };
|
||||
test_key_value_pair(magic_foo);
|
||||
|
||||
return boost::report_errors();
|
||||
}
|
33
initialized_test_fail1.cpp
Normal file
33
initialized_test_fail1.cpp
Normal file
@ -0,0 +1,33 @@
|
||||
// Copyright 2010, Niels Dekker.
|
||||
//
|
||||
// Distributed under the Boost Software License, Version 1.0. (See
|
||||
// accompanying file LICENSE_1_0.txt or copy at
|
||||
// http://www.boost.org/LICENSE_1_0.txt)
|
||||
//
|
||||
// Test program for boost::initialized<T>. Must fail to compile.
|
||||
//
|
||||
// Initial: 2 May 2010
|
||||
|
||||
#include <boost/utility/value_init.hpp>
|
||||
|
||||
namespace
|
||||
{
|
||||
void direct_initialize_from_int()
|
||||
{
|
||||
// Okay: initialized<T> supports direct-initialization from T.
|
||||
boost::initialized<int> direct_initialized_int(1);
|
||||
}
|
||||
|
||||
void copy_initialize_from_int()
|
||||
{
|
||||
// The following line should not compile, because initialized<T>
|
||||
// was not intended to supports copy-initialization from T.
|
||||
boost::initialized<int> copy_initialized_int = 1;
|
||||
}
|
||||
}
|
||||
|
||||
int main()
|
||||
{
|
||||
// This should fail to compile, so there is no need to call any function.
|
||||
return 0;
|
||||
}
|
37
initialized_test_fail2.cpp
Normal file
37
initialized_test_fail2.cpp
Normal file
@ -0,0 +1,37 @@
|
||||
// Copyright 2010, Niels Dekker.
|
||||
//
|
||||
// Distributed under the Boost Software License, Version 1.0. (See
|
||||
// accompanying file LICENSE_1_0.txt or copy at
|
||||
// http://www.boost.org/LICENSE_1_0.txt)
|
||||
//
|
||||
// Test program for boost::initialized<T>. Must fail to compile.
|
||||
//
|
||||
// Initial: 2 May 2010
|
||||
|
||||
#include <boost/utility/value_init.hpp>
|
||||
|
||||
namespace
|
||||
{
|
||||
void from_value_initialized_to_initialized()
|
||||
{
|
||||
boost::value_initialized<int> value_initialized_int;
|
||||
|
||||
// Okay: initialized<T> can be initialized by value_initialized<T>.
|
||||
boost::initialized<int> initialized_int(value_initialized_int);
|
||||
}
|
||||
|
||||
void from_initialized_to_value_initialized()
|
||||
{
|
||||
boost::initialized<int> initialized_int(13);
|
||||
|
||||
// The following line should not compile, because initialized<T>
|
||||
// should not be convertible to value_initialized<T>.
|
||||
boost::value_initialized<int> value_initialized_int(initialized_int);
|
||||
}
|
||||
}
|
||||
|
||||
int main()
|
||||
{
|
||||
// This should fail to compile, so there is no need to call any function.
|
||||
return 0;
|
||||
}
|
@ -1 +0,0 @@
|
||||
boost_module(utility DEPENDS iterator exception detail )
|
43
ref_test.cpp
43
ref_test.cpp
@ -68,11 +68,54 @@ struct ref_wrapper
|
||||
}
|
||||
};
|
||||
|
||||
struct copy_counter {
|
||||
static int count_;
|
||||
copy_counter(copy_counter const& /*other*/) {
|
||||
++count_;
|
||||
}
|
||||
copy_counter() {}
|
||||
static void reset() { count_ = 0; }
|
||||
static int count() { return copy_counter::count_; }
|
||||
};
|
||||
|
||||
int copy_counter::count_ = 0;
|
||||
|
||||
} // namespace unnamed
|
||||
|
||||
template <class T>
|
||||
void do_unwrap(T t) {
|
||||
|
||||
/* typename unwrap_reference<T>::type& lt = */
|
||||
unwrap_ref(t);
|
||||
|
||||
}
|
||||
|
||||
void unwrap_test() {
|
||||
|
||||
int i = 3;
|
||||
const int ci = 2;
|
||||
|
||||
do_unwrap(i);
|
||||
do_unwrap(ci);
|
||||
do_unwrap(ref(i));
|
||||
do_unwrap(cref(ci));
|
||||
do_unwrap(ref(ci));
|
||||
|
||||
copy_counter cc;
|
||||
BOOST_CHECK(cc.count() == 0);
|
||||
|
||||
do_unwrap(cc);
|
||||
do_unwrap(ref(cc));
|
||||
do_unwrap(cref(cc));
|
||||
|
||||
BOOST_CHECK(cc.count() == 1);
|
||||
BOOST_CHECK(unwrap_ref(ref(cc)).count() == 1);
|
||||
}
|
||||
|
||||
int test_main(int, char * [])
|
||||
{
|
||||
ref_wrapper<int>::test(1);
|
||||
ref_wrapper<int const>::test(1);
|
||||
unwrap_test();
|
||||
return 0;
|
||||
}
|
||||
|
@ -7,7 +7,11 @@
|
||||
</head>
|
||||
<body>
|
||||
<!-- Page header -->
|
||||
<h2>
|
||||
<img src="../../boost.png" alt="C++ Boost" align="middle" width="277" height="86"/>
|
||||
Header <<a href="../../boost/swap.hpp">boost/swap.hpp</a>>
|
||||
</h2>
|
||||
|
||||
<h1>Swap</h1>
|
||||
|
||||
<p>
|
||||
@ -84,9 +88,9 @@
|
||||
|
||||
<!-- Copyright info -->
|
||||
<hr/>
|
||||
<p>Revised: 15 November 2008</p>
|
||||
<p>Revised: 08 September 2009</p>
|
||||
<p>
|
||||
Copyright 2007, 2008 Joseph Gauterin. Use, modification, and distribution are subject to the Boost Software License, Version 1.0.
|
||||
Copyright 2007 - 2009 Joseph Gauterin. Use, modification, and distribution are subject to the Boost Software License, Version 1.0.
|
||||
(See accompanying file <a href="../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or a copy at <<a href="http://www.boost.org/LICENSE_1_0.txt">http://www.boost.org/LICENSE_1_0.txt</a>>.)
|
||||
</p>
|
||||
|
||||
|
@ -1,41 +0,0 @@
|
||||
#
|
||||
# Copyright Troy D. Straszheim
|
||||
#
|
||||
# Distributed under the Boost Software License, Version 1.0.
|
||||
# See http://www.boost.org/LICENSE_1_0.txt
|
||||
#
|
||||
|
||||
foreach(T
|
||||
root_header_1 root_header_2
|
||||
lib_header_1 lib_header_2
|
||||
mixed_headers_1 mixed_headers_2)
|
||||
boost_test_compile(${T})
|
||||
endforeach()
|
||||
|
||||
|
||||
# [ run primitive.cpp ../../../test/build//boost_test_exec_monitor/<link>static ]
|
||||
|
||||
|
||||
foreach(T
|
||||
primitive
|
||||
specialized_in_boost
|
||||
specialized_in_global
|
||||
specialized_in_other
|
||||
specialized_in_std
|
||||
specialized_in_boost_and_other
|
||||
std_bitset
|
||||
std_dateorder
|
||||
std_string
|
||||
std_typeinfo_ptr
|
||||
std_vector_of_boost
|
||||
std_vector_of_global
|
||||
std_vector_of_other
|
||||
no_ambiguity_in_boost
|
||||
array_of_array_of_class
|
||||
array_of_array_of_int
|
||||
array_of_class
|
||||
array_of_int
|
||||
array_of_template)
|
||||
boost_test_run(${T} DEPENDS boost_test_exec_monitor)
|
||||
endforeach()
|
||||
|
@ -1,4 +1,4 @@
|
||||
// Copyright (c) 2008 Joseph Gauterin, Niels Dekker
|
||||
// Copyright (c) 2008 - 2010 Joseph Gauterin, Niels Dekker
|
||||
//
|
||||
// Distributed under the Boost Software License, Version 1.0.
|
||||
// (See accompanying file LICENSE_1_0.txt or copy at
|
||||
@ -17,8 +17,8 @@
|
||||
int test_main(int, char*[])
|
||||
{
|
||||
typedef std::bitset<8> bitset_type;
|
||||
const bitset_type initial_value1 = 1ul;
|
||||
const bitset_type initial_value2 = 2ul;
|
||||
const bitset_type initial_value1 = 1;
|
||||
const bitset_type initial_value2 = 2;
|
||||
|
||||
bitset_type object1 = initial_value1;
|
||||
bitset_type object2 = initial_value2;
|
||||
|
@ -1,47 +0,0 @@
|
||||
#
|
||||
# Copyright Troy D. Straszheim
|
||||
#
|
||||
# Distributed under the Boost Software License, Version 1.0.
|
||||
# See http://www.boost.org/LICENSE_1_0.txt
|
||||
#
|
||||
boost_additional_test_dependencies(utility BOOST_DEPENDS test)
|
||||
|
||||
boost_test_run(addressof_fn_test ../addressof_fn_test.cpp)
|
||||
boost_test_run(addressof_test ../addressof_test.cpp)
|
||||
boost_test_run(addressof_test2 ../addressof_test2.cpp)
|
||||
boost_test_run(assert_test ../assert_test.cpp)
|
||||
boost_test_run(base_from_member_test ../base_from_member_test.cpp)
|
||||
boost_test_run(binary_search_test ../binary_search_test.cpp)
|
||||
boost_test_run(call_traits_test ../call_traits_test.cpp ARGS -u)
|
||||
boost_test_compile_fail(checked_delete_test ../checked_delete_test.cpp)
|
||||
boost_test_run(compressed_pair_test
|
||||
../compressed_pair_test
|
||||
DEPENDS boost_test_exec_monitor)
|
||||
boost_test_run(current_function_test ../current_function_test.cpp)
|
||||
boost_test_run(iterators_test
|
||||
../iterators_test.cpp
|
||||
DEPENDS boost_test_exec_monitor)
|
||||
boost_test_run(next_prior_test DEPENDS boost_test_exec_monitor)
|
||||
boost_test_compile_fail(noncopyable_test ../noncopyable_test.cpp)
|
||||
boost_test_run(numeric_traits_test ../numeric_traits_test.cpp)
|
||||
if (${CMAKE_SYSTEM} MATCHES "FreeBSD-.*")
|
||||
boost_test_compile_fail("operators_test_compilerbug")
|
||||
elseif(${CMAKE_SYSTEM} MATCHES "FreeBSD-.*")
|
||||
boost_test_run(operators_test
|
||||
../operators_test.cpp
|
||||
DEPENDS boost_test_exec_monitor)
|
||||
endif(${CMAKE_SYSTEM} MATCHES "FreeBSD-.*")
|
||||
boost_test_compile(ref_ct_test ../ref_ct_test.cpp)
|
||||
boost_test_run(ref_test
|
||||
../ref_test.cpp
|
||||
DEPENDS boost_test_exec_monitor)
|
||||
boost_test_compile(result_of_test)
|
||||
boost_test_run(shared_iterator_test ../shared_iterator_test.cpp)
|
||||
boost_test_run(value_init_test ../value_init_test.cpp)
|
||||
boost_test_compile_fail(value_init_test_fail1
|
||||
../value_init_test_fail1.cpp)
|
||||
boost_test_compile_fail(value_init_test_fail2
|
||||
../value_init_test_fail2.cpp)
|
||||
boost_test_compile_fail(value_init_test_fail3
|
||||
../value_init_test_fail3.cpp)
|
||||
boost_test_run(verify_test ../verify_test.cpp)
|
@ -32,9 +32,13 @@ test-suite utility
|
||||
[ compile result_of_test.cpp ]
|
||||
[ run ../shared_iterator_test.cpp ]
|
||||
[ run ../value_init_test.cpp ]
|
||||
[ run ../value_init_workaround_test.cpp ]
|
||||
[ run ../initialized_test.cpp ]
|
||||
[ compile-fail ../value_init_test_fail1.cpp ]
|
||||
[ compile-fail ../value_init_test_fail2.cpp ]
|
||||
[ compile-fail ../value_init_test_fail3.cpp ]
|
||||
[ compile-fail ../initialized_test_fail1.cpp ]
|
||||
[ compile-fail ../initialized_test_fail2.cpp ]
|
||||
[ run ../verify_test.cpp ]
|
||||
;
|
||||
|
||||
|
0
test/next_prior_test.cpp
Executable file → Normal file
0
test/next_prior_test.cpp
Executable file → Normal file
@ -5,41 +5,109 @@
|
||||
// 1.0. (See accompanying file LICENSE_1_0.txt or copy at
|
||||
// http://www.boost.org/LICENSE_1_0.txt)
|
||||
|
||||
#define BOOST_RESULT_OF_USE_DECLTYPE
|
||||
|
||||
// For more information, see http://www.boost.org/libs/utility
|
||||
#include <boost/utility/result_of.hpp>
|
||||
#include <utility>
|
||||
#include <boost/static_assert.hpp>
|
||||
#include <boost/type_traits/is_same.hpp>
|
||||
|
||||
struct int_result_type { typedef int result_type; };
|
||||
struct int_result_type
|
||||
{
|
||||
typedef int result_type;
|
||||
result_type operator()(float);
|
||||
};
|
||||
|
||||
struct int_result_of
|
||||
{
|
||||
template<typename F> struct result { typedef int type; };
|
||||
result<int_result_of(double)>::type operator()(double);
|
||||
result<const int_result_of(double)>::type operator()(double) const;
|
||||
result<int_result_of()>::type operator()();
|
||||
result<volatile int_result_of()>::type operator()() volatile;
|
||||
};
|
||||
|
||||
struct int_result_type_and_float_result_of
|
||||
struct int_result_type_and_float_result_of_and_char_return
|
||||
{
|
||||
typedef int result_type;
|
||||
template<typename F> struct result { typedef float type; };
|
||||
char operator()(char);
|
||||
};
|
||||
|
||||
template<typename T>
|
||||
struct int_result_type_template { typedef int result_type; };
|
||||
struct int_result_type_template
|
||||
{
|
||||
typedef int result_type;
|
||||
result_type operator()(float);
|
||||
};
|
||||
|
||||
template<typename T>
|
||||
struct int_result_of_template
|
||||
{
|
||||
template<typename F> struct result;
|
||||
template<typename This, typename That> struct result<This(That)> { typedef int type; };
|
||||
typename result<int_result_of_template<T>(double)>::type operator()(double);
|
||||
typename result<const int_result_of_template<T>(double)>::type operator()(double) const;
|
||||
typename result<int_result_of_template<T>(double)>::type operator()();
|
||||
typename result<volatile int_result_of_template<T>(double)>::type operator()() volatile;
|
||||
};
|
||||
|
||||
template<typename T>
|
||||
struct int_result_type_and_float_result_of_template
|
||||
struct int_result_type_and_float_result_of_and_char_return_template
|
||||
{
|
||||
typedef int result_type;
|
||||
template<typename F> struct result;
|
||||
template<typename This, typename That> struct result<This(That)> { typedef float type; };
|
||||
char operator()(char);
|
||||
};
|
||||
|
||||
struct result_of_member_function_template
|
||||
{
|
||||
template<typename F> struct result;
|
||||
|
||||
template<typename This, typename That> struct result<This(That)> { typedef That type; };
|
||||
template<class T> typename result<result_of_member_function_template(T)>::type operator()(T);
|
||||
|
||||
template<typename This, typename That> struct result<const This(That)> { typedef const That type; };
|
||||
template<class T> typename result<const result_of_member_function_template(T)>::type operator()(T) const;
|
||||
|
||||
template<typename This, typename That> struct result<volatile This(That)> { typedef volatile That type; };
|
||||
template<class T> typename result<volatile result_of_member_function_template(T)>::type operator()(T) volatile;
|
||||
|
||||
template<typename This, typename That> struct result<const volatile This(That)> { typedef const volatile That type; };
|
||||
template<class T> typename result<const volatile result_of_member_function_template(T)>::type operator()(T) const volatile;
|
||||
|
||||
template<typename This, typename That> struct result<This(That &, That)> { typedef That & type; };
|
||||
template<class T> typename result<result_of_member_function_template(T &, T)>::type operator()(T &, T);
|
||||
|
||||
template<typename This, typename That> struct result<This(That const &, That)> { typedef That const & type; };
|
||||
template<class T> typename result<result_of_member_function_template(T const &, T)>::type operator()(T const &, T);
|
||||
|
||||
template<typename This, typename That> struct result<This(That volatile &, That)> { typedef That volatile & type; };
|
||||
template<class T> typename result<result_of_member_function_template(T volatile &, T)>::type operator()(T volatile &, T);
|
||||
|
||||
template<typename This, typename That> struct result<This(That const volatile &, That)> { typedef That const volatile & type; };
|
||||
template<class T> typename result<result_of_member_function_template(T const volatile &, T)>::type operator()(T const volatile &, T);
|
||||
};
|
||||
|
||||
struct no_result_type_or_result_of
|
||||
{
|
||||
int operator()(double);
|
||||
short operator()(double) const;
|
||||
unsigned int operator()();
|
||||
unsigned short operator()() volatile;
|
||||
const unsigned short operator()() const volatile;
|
||||
};
|
||||
|
||||
template<typename T>
|
||||
struct no_result_type_or_result_of_template
|
||||
{
|
||||
int operator()(double);
|
||||
short operator()(double) const;
|
||||
unsigned int operator()();
|
||||
unsigned short operator()() volatile;
|
||||
const unsigned short operator()() const volatile;
|
||||
};
|
||||
|
||||
struct X {};
|
||||
@ -60,16 +128,52 @@ int main()
|
||||
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<int_result_type(float)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<int_result_of(double)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<int_result_of(void)>::type, void>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<const int_result_of(double)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<volatile int_result_of(void)>::type, void>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<int_result_type_and_float_result_of(char)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<int_result_type_template<void>(float)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<int_result_of_template<void>(double)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<int_result_of_template<void>(void)>::type, void>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<const int_result_of_template<void>(double)>::type, int>::value));
|
||||
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<int_result_type(float)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<int_result_of(double)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<const int_result_of(double)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<int_result_type_template<void>(float)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<int_result_of_template<void>(double)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<const int_result_of_template<void>(double)>::type, int>::value));
|
||||
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<int_result_of(void)>::type, void>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<volatile int_result_of(void)>::type, void>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<int_result_of_template<void>(void)>::type, void>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<volatile int_result_of_template<void>(void)>::type, void>::value));
|
||||
|
||||
// Prior to decltype, result_of could not deduce the return type
|
||||
// nullary function objects unless they exposed a result_type.
|
||||
#if !defined(BOOST_NO_DECLTYPE)
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<int_result_of(void)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<volatile int_result_of(void)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<int_result_of_template<void>(void)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<volatile int_result_of_template<void>(void)>::type, int>::value));
|
||||
#else
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<int_result_of(void)>::type, void>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<volatile int_result_of(void)>::type, void>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<int_result_of_template<void>(void)>::type, void>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<volatile int_result_of_template<void>(void)>::type, void>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<int_result_type_and_float_result_of_template<void>(char)>::type, int>::value));
|
||||
#endif
|
||||
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<int_result_type_and_float_result_of_and_char_return(char)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<int_result_type_and_float_result_of_and_char_return_template<void>(char)>::type, int>::value));
|
||||
|
||||
// Prior to decltype, result_of ignored a nested result<> if
|
||||
// result_type was defined. After decltype, result_of deduces the
|
||||
// actual return type of the function object, ignoring both
|
||||
// result<> and result_type.
|
||||
#if !defined(BOOST_NO_DECLTYPE)
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<int_result_type_and_float_result_of_and_char_return(char)>::type, char>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<int_result_type_and_float_result_of_and_char_return_template<void>(char)>::type, char>::value));
|
||||
#else
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<int_result_type_and_float_result_of_and_char_return(char)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<int_result_type_and_float_result_of_and_char_return_template<void>(char)>::type, int>::value));
|
||||
#endif
|
||||
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<func_ptr(char, float)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<func_ref(char, float)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<func_ptr_0()>::type, int>::value));
|
||||
@ -81,5 +185,54 @@ int main()
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<mem_func_ptr_0(X)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<func_ptr(void)>::type, int>::value));
|
||||
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<func_ptr(char, float)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<func_ref(char, float)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<func_ptr_0()>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<func_ref_0()>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<mem_func_ptr(X,char)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<mem_func_ptr_c(X,char)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<mem_func_ptr_v(X,char)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<mem_func_ptr_cv(X,char)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<mem_func_ptr_0(X)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<func_ptr(void)>::type, int>::value));
|
||||
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<result_of_member_function_template(double)>::type, double>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<const result_of_member_function_template(double)>::type, const double>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<volatile result_of_member_function_template(double)>::type, volatile double>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<const volatile result_of_member_function_template(double)>::type, const volatile double>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<result_of_member_function_template(int &, int)>::type, int &>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<result_of_member_function_template(int const &, int)>::type, int const &>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<result_of_member_function_template(int volatile &, int)>::type, int volatile &>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<result_of_member_function_template(int const volatile &, int)>::type, int const volatile &>::value));
|
||||
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<result_of_member_function_template(double)>::type, double>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<const result_of_member_function_template(double)>::type, const double>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<volatile result_of_member_function_template(double)>::type, volatile double>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<const volatile result_of_member_function_template(double)>::type, const volatile double>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<result_of_member_function_template(int &, int)>::type, int &>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<result_of_member_function_template(int const &, int)>::type, int const &>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<result_of_member_function_template(int volatile &, int)>::type, int volatile &>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<result_of_member_function_template(int const volatile &, int)>::type, int const volatile &>::value));
|
||||
|
||||
typedef int (*pf_t)(int);
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<pf_t(int)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<pf_t const(int)>::type,int>::value));
|
||||
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<pf_t(int)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<tr1_result_of<pf_t const(int)>::type,int>::value));
|
||||
|
||||
#if !defined(BOOST_NO_DECLTYPE)
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<no_result_type_or_result_of(double)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<no_result_type_or_result_of(void)>::type, unsigned int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<const no_result_type_or_result_of(double)>::type, short>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<volatile no_result_type_or_result_of(void)>::type, unsigned short>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<const volatile no_result_type_or_result_of(void)>::type, const unsigned short>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<no_result_type_or_result_of_template<void>(double)>::type, int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<no_result_type_or_result_of_template<void>(void)>::type, unsigned int>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<const no_result_type_or_result_of_template<void>(double)>::type, short>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<volatile no_result_type_or_result_of_template<void>(void)>::type, unsigned short>::value));
|
||||
BOOST_STATIC_ASSERT((is_same<result_of<const volatile no_result_type_or_result_of_template<void>(void)>::type, const unsigned short>::value));
|
||||
#endif
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
206
value_init.htm
206
value_init.htm
@ -33,6 +33,7 @@
|
||||
|
||||
<ul>
|
||||
<li><a href="#val_init"><code>template class value_initialized<T></code></a></li>
|
||||
<li><a href="#initialized"><code>template class initialized<T></code></a></li>
|
||||
<li><a href="#initialized_value"><code>initialized_value</code></a></li>
|
||||
|
||||
</ul>
|
||||
@ -123,6 +124,12 @@ constructed by the following declaration:
|
||||
</pre>
|
||||
</p>
|
||||
<p>
|
||||
The template <a href="#initialized"><code>initialized</code></a>
|
||||
offers both value-initialization and direct-initialization.
|
||||
It is especially useful as a data member type, allowing the very same object
|
||||
to be either direct-initialized or value-initialized.
|
||||
</p>
|
||||
<p>
|
||||
The <code>const</code> object <a href="#initialized_value"><code>initialized_value</code></a>
|
||||
allows value-initializing a variable as follows:
|
||||
<pre>
|
||||
@ -216,44 +223,98 @@ it <em>may</em> in practice still be left uninitialized, because of those
|
||||
compiler issues! It's hard to make a general statement on what those issues
|
||||
are like, because they depend on the compiler you are using, its version number,
|
||||
and the type of object you would like to have value-initialized.
|
||||
Compilers usually support value-initialization for built-in types properly.
|
||||
But objects of user-defined types that involve <em>aggregates</em> may <em>in some cases</em>
|
||||
be partially, or even entirely left uninitialized, when they should be value-initialized.
|
||||
All compilers we have tested so far support value-initialization for arithmetic types properly.
|
||||
However, various compilers may leave some types of <em>aggregates</em> uninitialized, when they
|
||||
should be value-initialized. Value-initialization of objects of a pointer-to-member type may also
|
||||
go wrong on various compilers.
|
||||
</p>
|
||||
<p>
|
||||
We have encountered issues regarding value-initialization on compilers by
|
||||
Microsoft, Sun, Borland, and GNU. Here is a list of bug reports on those issues:
|
||||
<table summary="Compiler bug reports regarding value-initialization" border="0" cellpadding="7" cellspacing="1" >
|
||||
<tr><td>
|
||||
<a href="https://connect.microsoft.com/VisualStudio/feedback/ViewFeedback.aspx?FeedbackID=100744">
|
||||
Microsoft Feedback ID 100744 - Value-initialization in new-expression</a>
|
||||
<br>Reported by Pavel Kuznetsov (MetaCommunications Engineering), 2005-07-28
|
||||
<br>
|
||||
<a href="http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30111">
|
||||
GCC Bug 30111 - Value-initialization of POD base class doesn't initialize members</a>
|
||||
<br>Reported by Jonathan Wakely, 2006-12-07
|
||||
<br>
|
||||
<a href="http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33916">
|
||||
GCC Bug 33916 - Default constructor fails to initialize array members</a>
|
||||
<br>Reported by Michael Elizabeth Chastain, 2007-10-26
|
||||
<br>
|
||||
<a href="http://qc.codegear.com/wc/qcmain.aspx?d=51854">
|
||||
Borland Report 51854 - Value-initialization: POD struct should be zero-initialized</a>
|
||||
<br>Reported by Niels Dekker (LKEB, Leiden University Medical Center), 2007-09-11
|
||||
<br>
|
||||
</td></tr></table>
|
||||
At the moment of writing, May 2010, the following reported issues regarding
|
||||
value-initialization are still there in current compiler releases:
|
||||
<ul>
|
||||
<li>
|
||||
<a href="https://connect.microsoft.com/VisualStudio/feedback/details/100744">
|
||||
Microsoft Visual Studio Feedback ID 100744, Value-initialization in new-expression</a>
|
||||
<br>Reported by Pavel Kuznetsov (MetaCommunications Engineering), 2005
|
||||
</li><li>
|
||||
<a href="http://connect.microsoft.com/VisualStudio/feedback/details/484295">
|
||||
Microsoft Visual Studio Feedback ID 484295, VC++ does not value-initialize members of derived classes without user-declared constructor</a>
|
||||
<br>Reported by Sylvester Hesp, 2009
|
||||
</li><li>
|
||||
<a href="https://connect.microsoft.com/VisualStudio/feedback/details/499606">
|
||||
Microsoft Visual Studio Feedback ID 499606, Presence of copy constructor breaks member class initialization</a>
|
||||
<br>Reported by Alex Vakulenko, 2009
|
||||
</li><li>
|
||||
<a href="http://qc.embarcadero.com/wc/qcmain.aspx?d=83751">
|
||||
Embarcadero/C++Builder Report 83751, Value-initialization: arrays should have each element value-initialized</a>
|
||||
<br>Reported by Niels Dekker (LKEB), 2010
|
||||
</li><li>
|
||||
<a href="http://qc.embarcadero.com/wc/qcmain.aspx?d=83851">
|
||||
Embarcadero/C++Builder Report 83851, Value-initialized temporary triggers internal backend error C1798</a>
|
||||
<br>Reported by Niels Dekker, 2010
|
||||
</li><li>
|
||||
<a href="http://qc.embarcadero.com/wc/qcmain.aspx?d=84279">
|
||||
Embarcadero/C++Builder Report 84279, Internal compiler error (F1004), value-initializing member function pointer by "new T()"</a>
|
||||
<br>Reported by Niels Dekker, 2010
|
||||
</li><li>
|
||||
Sun CR 6947016, Sun 5.10 may fail to value-initialize an object of a non-POD aggregate.
|
||||
<br>Reported to Steve Clamage by Niels Dekker, 2010
|
||||
</li><li>
|
||||
IBM's XL V10.1 and V11.1 may fail to value-initialize a temporary of a non-POD aggregate.
|
||||
<br>Reported to Michael Wong by Niels Dekker, 2010
|
||||
</li><li>
|
||||
Intel support issue 589832, Attempt to value-initialize pointer-to-member triggers internal error
|
||||
on Intel 11.1.
|
||||
<br>Reported by John Maddock, 2010
|
||||
</li>
|
||||
</ul>
|
||||
Note that all known GCC issues regarding value-initialization are
|
||||
fixed with GCC version 4.4, including
|
||||
<a href="http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30111">GCC Bug 30111</a>.
|
||||
Clang also has completely implemented value-initialization, as far as we know,
|
||||
now that <a href="http://llvm.org/bugs/show_bug.cgi?id=7139">Clang Bug 7139</a> is fixed.
|
||||
</p><p>
|
||||
|
||||
New versions of <code>value_initialized</code>
|
||||
(Boost release version 1.35 or higher)
|
||||
offer a workaround to these issues: <code>value_initialized</code> will now clear
|
||||
its internal data, prior to constructing the object that it contains.
|
||||
offer a workaround to these issues: <code>value_initialized</code> may now clear
|
||||
its internal data, prior to constructing the object that it contains. It will do
|
||||
so for those compilers that need to have such a workaround, based on the
|
||||
<a href="../config/doc/html/boost_config/boost_macro_reference.html#boost_config.boost_macro_reference.macros_that_describe_defects"
|
||||
>compiler defect macro</a> BOOST_NO_COMPLETE_VALUE_INITIALIZATION.
|
||||
</p>
|
||||
|
||||
<h2><a name="types"></a>Types and objects</h2>
|
||||
|
||||
<h2><a name="val_init"><code>template class value_initialized<T></code></a></h2>
|
||||
|
||||
<pre>namespace boost {<br><br>template<class T><br>class value_initialized<br>{<br> public :<br> value_initialized() : x() {}<br> operator T&() const { return x ; }<br> T& data() const { return x ; }<br> void swap( value_initialized<T>& );<br><br> private :<br> <i>unspecified</i> x ;<br>} ;<br><br>template<class T><br>T const& get ( value_initialized<T> const& x )<br>{<br> return x.data() ;<br>}<br><br>template<class T><br>T& get ( value_initialized<T>& x )<br>{<br> return x.data() ;<br>}<br><br>} // namespace boost<br></pre>
|
||||
<pre>namespace boost {<br><br>template<class T><br>class value_initialized<br>{
|
||||
<br> public :
|
||||
<br> value_initialized() : x() {}
|
||||
<br> operator T const &() const { return x ; }
|
||||
<br> operator T&() { return x ; }
|
||||
<br> T const &data() const { return x ; }
|
||||
<br> T& data() { return x ; }
|
||||
<br> void swap( value_initialized<T>& );
|
||||
<br>
|
||||
<br> private :
|
||||
<br> <i>unspecified</i> x ;
|
||||
<br>} ;
|
||||
<br>
|
||||
<br>template<class T>
|
||||
<br>T const& get ( value_initialized<T> const& x )
|
||||
<br>{
|
||||
<br> return x.data() ;
|
||||
<br>}
|
||||
<br>
|
||||
<br>template<class T>
|
||||
<br>T& get ( value_initialized<T>& x )
|
||||
<br>{
|
||||
<br> return x.data() ;
|
||||
<br>}
|
||||
<br>
|
||||
<br>} // namespace boost
|
||||
<br></pre>
|
||||
|
||||
<p>An object of this template class is a <code>T</code>-wrapper convertible
|
||||
to <code>'T&'</code> whose wrapped object (data member of type <code>T</code>)
|
||||
@ -271,7 +332,8 @@ its internal data, prior to constructing the object that it contains.
|
||||
<code>T&</code>, the member function <code>data()</code>, or the
|
||||
non-member function <code>get()</code>: </p>
|
||||
|
||||
<pre>void watch(int);<br>value_initialized<int> x;<br><br>watch(x) ; // operator T& used.<br>watch(x.data());<br>watch( get(x) ) // function get() used</pre>
|
||||
<pre>void watch(int);<br>value_initialized<int> x;
|
||||
<br><br>watch(x) ; // operator T& used.<br>watch(x.data());<br>watch( get(x) ) // function get() used</pre>
|
||||
|
||||
<p>Both <code>const</code> and non-<code>const</code> objects can be wrapped.
|
||||
Mutable objects can be modified directly from within the wrapper but constant
|
||||
@ -281,41 +343,84 @@ non-member function <code>get()</code>: </p>
|
||||
is swappable as well, by calling its <code>swap</code> member function
|
||||
as well as by calling <code>boost::swap</code>.</p>
|
||||
|
||||
<pre>value_initialized<int> x ; <br>static_cast<int&>(x) = 1 ; // OK<br>get(x) = 1 ; // OK<br><br>value_initialized<int const> y ; <br>static_cast<int&>(y) = 1 ; // ERROR: cannot cast to int&<br>static_cast<int const&>(y) = 1 ; // ERROR: cannot modify a const value<br>get(y) = 1 ; // ERROR: cannot modify a const value</pre>
|
||||
<pre>value_initialized<int> x ; <br>static_cast<int&>(x) = 1 ; // OK<br>get(x) = 1 ; // OK
|
||||
<br><br>value_initialized<int const> y ; <br>static_cast<int&>(y) = 1 ; // ERROR: cannot cast to int&<br>static_cast<int const&>(y) = 1 ; // ERROR: cannot modify a const value<br>get(y) = 1 ; // ERROR: cannot modify a const value</pre>
|
||||
|
||||
<h3>Warning:</h3>
|
||||
|
||||
<p>Both the conversion operator and the <code>data()</code> member function
|
||||
are <code>const</code> in order to allow access to the wrapped object
|
||||
from a constant wrapper:</p>
|
||||
<p>The <code>value_initialized</code> implementation of Boost version 1.40.0 and older
|
||||
allowed <i>non-const</i> access to the wrapped object, from a constant wrapper,
|
||||
both by its conversion operator and its <code>data()</code> member function. For example:</p>
|
||||
|
||||
<pre>void foo(int);<br>value_initialized<int> const x ;<br>foo(x);<br></pre>
|
||||
<pre>value_initialized<int> const x_c ;<br>int& xr = x_c ; // OK, conversion to int& available even though x_c is itself const.
|
||||
<br>xr = 2 ; </pre>
|
||||
|
||||
<p>But notice that this conversion operator is to <code>T&</code> although
|
||||
it is itself <code>const</code>. As a consequence, if <code>T</code> is
|
||||
a non-<code>const</code> type, you can modify the wrapped object even from
|
||||
within a constant wrapper:</p>
|
||||
|
||||
<pre>value_initialized<int> const x_c ;<br>int& xr = x_c ; // OK, conversion to int& available even though x_c is itself const.<br>xr = 2 ; </pre>
|
||||
|
||||
<p>The reason for this obscure behavior is that some commonly used compilers
|
||||
just don't accept the following valid code:</p>
|
||||
<p>The reason for this obscure behavior was that some compilers
|
||||
didn't accept the following valid code:</p>
|
||||
|
||||
<pre>struct X<br>{<br> operator int&() ;<br> operator int const&() const ; <br>};<br>X x ;<br>(x == 1 ) ; // ERROR HERE!</pre>
|
||||
|
||||
<p>These compilers complain about ambiguity between the conversion operators.
|
||||
This complaint is incorrect, but the only workaround that I know of is
|
||||
to provide only one of them, which leads to the obscure behavior just explained.<br>
|
||||
<p>The current version of <code>value_initialized</code> no longer has this obscure behavior.
|
||||
As compilers nowadays widely support overloading the conversion operator by having a <code>const</code> and a <code>non-const</code> version, we have decided to fix the issue accordingly. So the current version supports the idea of logical constness.
|
||||
<br>
|
||||
</p>
|
||||
|
||||
<h3>Recommended practice: The non-member get() idiom</h3>
|
||||
|
||||
<p>The obscure behavior of being able to modify a non-<code>const</code>
|
||||
wrapped object from within a constant wrapper can be avoided if access to
|
||||
wrapped object from within a constant wrapper (as was supported by previous
|
||||
versions of <code>value_initialized</code>)
|
||||
can be avoided if access to
|
||||
the wrapped object is always performed with the <code>get()</code> idiom:</p>
|
||||
|
||||
<pre>value_initialized<int> x ;<br>get(x) = 1 ; // OK<br><br>value_initialized<int const> cx ;<br>get(x) = 1 ; // ERROR: Cannot modify a const object<br><br>value_initialized<int> const x_c ;<br>get(x_c) = 1 ; // ERROR: Cannot modify a const object<br><br>value_initialized<int const> const cx_c ;<br>get(cx_c) = 1 ; // ERROR: Cannot modify a const object<br></pre>
|
||||
|
||||
<h2><a name="initialized"><code>template class initialized<T></code></a></h2>
|
||||
|
||||
<pre>namespace boost {<br><br>template<class T><br>class initialized<br>{
|
||||
<br> public :
|
||||
<br> initialized() : x() {}
|
||||
<br> explicit initialized(T const & arg) : x(arg) {}
|
||||
<br> operator T const &() const;
|
||||
<br> operator T&();
|
||||
<br> T const &data() const;
|
||||
<br> T& data();
|
||||
<br> void swap( value_initialized<T>& );
|
||||
<br>
|
||||
<br> private :
|
||||
<br> <i>unspecified</i> x ;
|
||||
<br>} ;
|
||||
<br>
|
||||
<br>template<class T>
|
||||
<br>T const& get ( initialized<T> const& x );
|
||||
<br>
|
||||
<br>template<class T>
|
||||
<br>T& get ( initialized<T>& x );
|
||||
<br>
|
||||
<br>} // namespace boost
|
||||
<br></pre>
|
||||
|
||||
The template class <code>boost::initialized<T></code> supports both value-initialization
|
||||
and direct-initialization, so its interface is a superset of the interface
|
||||
of <code>value_initialized<T></code>: Its default-constructor
|
||||
value-initializes the wrapped object just like the default-constructor of
|
||||
<code>value_initialized<T></code>, but <code>boost::initialized<T></code>
|
||||
also offers an extra <code>explicit</code>
|
||||
constructor, which direct-initializes the wrapped object by the specified value.
|
||||
<p>
|
||||
|
||||
<code>initialized<T></code> is especially useful when the wrapped
|
||||
object must be either value-initialized or direct-initialized, depending on
|
||||
runtime conditions. For example, <code>initialized<T></code> could
|
||||
hold the value of a data member that may be value-initialized by some
|
||||
constructors, and direct-initialized by others.
|
||||
On the other hand, if it is known beforehand that the
|
||||
object must <i>always</i> be value-initialized, <code>value_initialized<T></code>
|
||||
may be preferable. And if the object must always be
|
||||
direct-initialized, none of the two wrappers really needs to be used.
|
||||
</p>
|
||||
|
||||
|
||||
<h2><a name="initialized_value"><code>initialized_value</code></a></h2>
|
||||
|
||||
<pre>
|
||||
@ -375,6 +480,9 @@ Special thanks to Björn Karlsson who carefully edited and completed this do
|
||||
<p>value_initialized was reimplemented by Fernando Cacciola and Niels Dekker
|
||||
for Boost release version 1.35 (2008), offering a workaround to various compiler issues.
|
||||
</p>
|
||||
<p><code>boost::initialized</code> was very much inspired by feedback from Edward Diener and
|
||||
Jeffrey Hellrung.
|
||||
</p>
|
||||
<p>initialized_value was written by Niels Dekker, and added to Boost release version 1.36 (2008).
|
||||
</p>
|
||||
<p>Developed by <a href="mailto:fernando_cacciola@hotmail.com">Fernando Cacciola</a>,
|
||||
@ -383,9 +491,9 @@ for Boost release version 1.35 (2008), offering a workaround to various compiler
|
||||
</p>
|
||||
|
||||
<hr>
|
||||
<p>Revised 28 August 2008</p>
|
||||
<p>Revised 30 May 2010</p>
|
||||
|
||||
<p>© Copyright Fernando Cacciola, 2002, 2008.</p>
|
||||
<p>© Copyright Fernando Cacciola, 2002 - 2010.</p>
|
||||
|
||||
<p>Distributed under the Boost Software License, Version 1.0. See
|
||||
<a href="http://www.boost.org/LICENSE_1_0.txt">www.boost.org/LICENSE_1_0.txt</a></p>
|
||||
@ -394,4 +502,4 @@ for Boost release version 1.35 (2008), offering a workaround to various compiler
|
||||
<br>
|
||||
|
||||
</body>
|
||||
</html>
|
||||
</html>
|
||||
|
@ -29,9 +29,9 @@
|
||||
//
|
||||
struct POD
|
||||
{
|
||||
POD () : c(0), i(0), f(0) {}
|
||||
POD () : f(0), c(0), i(0){}
|
||||
|
||||
POD ( char c_, int i_, float f_ ) : c(c_), i(i_), f(f_) {}
|
||||
POD ( char c_, int i_, float f_ ) : f(f_), c(c_), i(i_) {}
|
||||
|
||||
friend std::ostream& operator << ( std::ostream& os, POD const& pod )
|
||||
{ return os << '(' << pod.c << ',' << pod.i << ',' << pod.f << ')' ; }
|
||||
@ -260,7 +260,7 @@ bool test ( T const& y, T const& z )
|
||||
boost::value_initialized<T> const x_c ;
|
||||
BOOST_CHECK ( y == x_c ) ;
|
||||
BOOST_CHECK ( y == boost::get(x_c) ) ;
|
||||
T& x_c_ref = x_c ;
|
||||
T& x_c_ref = const_cast<T&>( boost::get(x_c) ) ;
|
||||
x_c_ref = z ;
|
||||
BOOST_CHECK ( x_c == z ) ;
|
||||
|
||||
@ -291,7 +291,7 @@ int test_main(int, char **)
|
||||
{
|
||||
BOOST_CHECK ( test( 0,1234 ) ) ;
|
||||
BOOST_CHECK ( test( 0.0,12.34 ) ) ;
|
||||
BOOST_CHECK ( test( POD(0,0,0.0), POD('a',1234,56.78) ) ) ;
|
||||
BOOST_CHECK ( test( POD(0,0,0.0), POD('a',1234,56.78f) ) ) ;
|
||||
BOOST_CHECK ( test( NonPOD( std::string() ), NonPOD( std::string("something") ) ) ) ;
|
||||
|
||||
NonPOD NonPOD_object( std::string("NonPOD_object") );
|
||||
|
144
value_init_workaround_test.cpp
Normal file
144
value_init_workaround_test.cpp
Normal file
@ -0,0 +1,144 @@
|
||||
// Copyright 2010, Niels Dekker.
|
||||
//
|
||||
// Distributed under the Boost Software License, Version 1.0. (See
|
||||
// accompanying file LICENSE_1_0.txt or copy at
|
||||
// http://www.boost.org/LICENSE_1_0.txt)
|
||||
//
|
||||
// Test program for the boost::value_initialized<T> workaround.
|
||||
//
|
||||
// 17 June 2010 (Created) Niels Dekker
|
||||
|
||||
// Switch the workaround off, before inluding "value_init.hpp".
|
||||
#define BOOST_DETAIL_VALUE_INIT_WORKAROUND 0
|
||||
#include <boost/utility/value_init.hpp>
|
||||
|
||||
#include <iostream> // For cout.
|
||||
#include <cstdlib> // For EXIT_SUCCESS and EXIT_FAILURE.
|
||||
|
||||
namespace
|
||||
{
|
||||
struct empty_struct
|
||||
{
|
||||
};
|
||||
|
||||
// A POD aggregate struct derived from an empty struct.
|
||||
// Similar to struct Foo1 from Microsoft Visual C++ bug report 484295,
|
||||
// "VC++ does not value-initialize members of derived classes without
|
||||
// user-declared constructor", reported in 2009 by Sylvester Hesp:
|
||||
// https://connect.microsoft.com/VisualStudio/feedback/details/484295
|
||||
struct derived_struct: empty_struct
|
||||
{
|
||||
int data;
|
||||
};
|
||||
|
||||
bool is_value_initialized(const derived_struct& arg)
|
||||
{
|
||||
return arg.data == 0;
|
||||
}
|
||||
|
||||
|
||||
class virtual_destructor_holder
|
||||
{
|
||||
public:
|
||||
int i;
|
||||
virtual ~virtual_destructor_holder()
|
||||
{
|
||||
}
|
||||
};
|
||||
|
||||
bool is_value_initialized(const virtual_destructor_holder& arg)
|
||||
{
|
||||
return arg.i == 0;
|
||||
}
|
||||
|
||||
// Equivalent to the Stats class from GCC Bug 33916,
|
||||
// "Default constructor fails to initialize array members", reported in 2007 by
|
||||
// Michael Elizabeth Chastain: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33916
|
||||
// and fixed for GCC 4.2.4.
|
||||
class private_int_array_pair
|
||||
{
|
||||
friend bool is_value_initialized(const private_int_array_pair& arg);
|
||||
private:
|
||||
int first[12];
|
||||
int second[12];
|
||||
};
|
||||
|
||||
bool is_value_initialized(const private_int_array_pair& arg)
|
||||
{
|
||||
for ( unsigned i = 0; i < 12; ++i)
|
||||
{
|
||||
if ( (arg.first[i] != 0) || (arg.second[i] != 0) )
|
||||
{
|
||||
return false;
|
||||
}
|
||||
}
|
||||
return true;
|
||||
}
|
||||
|
||||
template <typename T>
|
||||
bool is_value_initialized(const T(& arg)[2])
|
||||
{
|
||||
return
|
||||
is_value_initialized(arg[0]) &&
|
||||
is_value_initialized(arg[1]);
|
||||
}
|
||||
|
||||
template <typename T>
|
||||
bool is_value_initialized(const boost::value_initialized<T>& arg)
|
||||
{
|
||||
return is_value_initialized(arg.data());
|
||||
}
|
||||
|
||||
// Returns zero when the specified object is value-initializated, and one otherwise.
|
||||
// Prints a message to standard output if the value-initialization has failed.
|
||||
template <class T>
|
||||
unsigned failed_to_value_initialized(const T& object, const char *const object_name)
|
||||
{
|
||||
if ( is_value_initialized(object) )
|
||||
{
|
||||
return 0u;
|
||||
}
|
||||
else
|
||||
{
|
||||
std::cout << "Note: Failed to value-initialize " << object_name << '.' << std::endl;
|
||||
return 1u;
|
||||
}
|
||||
}
|
||||
|
||||
// A macro that passed both the name and the value of the specified object to
|
||||
// the function above here.
|
||||
#define FAILED_TO_VALUE_INITIALIZE(value) failed_to_value_initialized(value, #value)
|
||||
|
||||
// Equivalent to the dirty_stack() function from GCC Bug 33916,
|
||||
// "Default constructor fails to initialize array members", reported in 2007 by
|
||||
// Michael Elizabeth Chastain: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33916
|
||||
void dirty_stack()
|
||||
{
|
||||
unsigned char array_on_stack[4096];
|
||||
for (unsigned i = 0; i < sizeof(array_on_stack); ++i)
|
||||
{
|
||||
array_on_stack[i] = 0x11;
|
||||
}
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
|
||||
int main()
|
||||
{
|
||||
dirty_stack();
|
||||
|
||||
// TODO More types may be added later.
|
||||
const unsigned num_failures =
|
||||
FAILED_TO_VALUE_INITIALIZE(boost::value_initialized<derived_struct>()) +
|
||||
FAILED_TO_VALUE_INITIALIZE(boost::value_initialized<virtual_destructor_holder[2]>()) +
|
||||
FAILED_TO_VALUE_INITIALIZE(boost::value_initialized<private_int_array_pair>());
|
||||
|
||||
#ifdef BOOST_DETAIL_VALUE_INIT_WORKAROUND_SUGGESTED
|
||||
// One or more failures are expected.
|
||||
return num_failures > 0 ? EXIT_SUCCESS : EXIT_FAILURE;
|
||||
#else
|
||||
// No failures are expected.
|
||||
return num_failures == 0 ? EXIT_SUCCESS : EXIT_FAILURE;
|
||||
#endif
|
||||
}
|
Reference in New Issue
Block a user