boostorg/optional
1
0
Fork 1
mirror of https://github.com/boostorg/optional.git synced 2025-07-29 20:17:21 +02:00
Code Issues Packages Projects Releases Wiki Activity

Partially added move semantics (tests are still failing)

Browse Source
This commit is contained in:
Andrzej Krzemienski
2014-04-22 22:36:19 +02:00
parent 587ef8e988
commit a26d11be87
4 changed files with 404 additions and 42 deletions
Download Patch File Download Diff File Expand all files Collapse all files

157
include/boost/optional/optional.hpp
View File

@ -26,7 +26,9 @@
#include <boost/type_traits/has_nothrow_constructor.hpp>
#include <boost/type_traits/type_with_alignment.hpp>
#include <boost/type_traits/remove_reference.hpp>
#include <boost/type_traits/decay.hpp>
#include <boost/type_traits/is_reference.hpp>
#include <boost/type_traits/is_same.hpp>
#include <boost/mpl/if.hpp>
#include <boost/mpl/bool.hpp>
#include <boost/mpl/not.hpp>
@ -36,6 +38,8 @@
#include <boost/utility/addressof.hpp>
#include <boost/utility/compare_pointees.hpp>
#include <boost/utility/in_place_factory.hpp>
#include <boost/utility/enable_if.hpp>
#include <boost/move/utility.hpp>
#include <boost/optional/optional_fwd.hpp>
@ -91,7 +95,8 @@ class in_place_factory_base ;
class typed_in_place_factory_base ;
// This forward is needed to refer to namespace scope swap from the member swap
template<class T> void swap ( optional<T>& x, optional<T>& y );
template<class T> void swap ( optional<T>& x, optional<T>& y )
BOOST_NOEXCEPT_IF(::boost::is_nothrow_move_constructible<T>::value && ::boost::is_nothrow_move_assignable<T>::value);
namespace optional_detail {
@ -225,7 +230,7 @@ class optional_base : public optional_tag
:
m_initialized(false)
{
construct( static_cast<T&&>(val) );
construct( boost::move(val) );
}
#endif
@ -257,10 +262,21 @@ class optional_base : public optional_tag
m_initialized(false)
{
if ( rhs.is_initialized() )
construct( static_cast<T&&>(rhs.get_impl()) );
construct( boost::move(rhs.get_impl()) );
}
#endif
#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
template<class Expr, typename PtrExpr>
explicit optional_base ( Expr&& expr, PtrExpr const* tag )
:
m_initialized(false)
{
construct(boost::forward<Expr>(expr),tag);
}
#else
// This is used for both converting and in-place constructions.
// Derived classes use the 'tag' to select the appropriate
// implementation (the correct 'construct()' overload)
@ -272,6 +288,7 @@ class optional_base : public optional_tag
construct(expr,tag);
}
#endif
// No-throw (assuming T::~T() doesn't)
@ -338,13 +355,13 @@ class optional_base : public optional_tag
else construct(val);
}
#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
// Assigns from a T (deep-moves the rhs value)
void assign ( rval_reference_type val )
{
if (is_initialized())
assign_value( static_cast<rval_reference_type>(val), is_reference_predicate() );
else construct( static_cast<rval_reference_type>(val) );
assign_value( boost::move(val), is_reference_predicate() );
else construct( boost::move(val) );
}
#endif
@ -353,13 +370,25 @@ class optional_base : public optional_tag
void assign ( none_t ) { destroy(); }
#ifndef BOOST_OPTIONAL_NO_INPLACE_FACTORY_SUPPORT
#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
template<class Expr, class ExprPtr>
void assign_expr ( Expr&& expr, ExprPtr const* tag )
{
if (is_initialized())
assign_expr_to_initialized(boost::forward<Expr>(expr),tag);
else construct(boost::forward<Expr>(expr),tag);
}
#else
template<class Expr>
void assign_expr ( Expr const& expr, Expr const* tag )
{
if (is_initialized())
assign_expr_to_initialized(expr,tag);
else construct(expr,tag);
}
{
if (is_initialized())
assign_expr_to_initialized(expr,tag);
else construct(expr,tag);
}
#endif
#endif
public :
@ -390,7 +419,7 @@ class optional_base : public optional_tag
#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
void construct ( rval_reference_type val )
{
new (m_storage.address()) internal_type( static_cast<rval_reference_type>(val) ) ;
new (m_storage.address()) internal_type( boost::move(val) ) ;
m_initialized = true ;
}
#endif
@ -430,7 +459,29 @@ class optional_base : public optional_tag
}
#endif
// Constructs using any expression implicitely convertible to the single argument
#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
// Constructs using any expression implicitly convertible to the single argument
// of a one-argument T constructor.
// Converting constructions of optional<T> from optional<U> uses this function with
// 'Expr' being of type 'U' and relying on a converting constructor of T from U.
template<class Expr>
void construct ( Expr&& expr, void const* )
{
new (m_storage.address()) internal_type(boost::forward<Expr>(expr)) ;
m_initialized = true ;
}
// Assigns using a form any expression implicitly convertible to the single argument
// of a T's assignment operator.
// Converting assignments of optional<T> from optional<U> uses this function with
// 'Expr' being of type 'U' and relying on a converting assignment of T from U.
template<class Expr>
void assign_expr_to_initialized ( Expr&& expr, void const* )
{
assign_value(boost::forward<Expr>(expr), is_reference_predicate());
}
#else
// Constructs using any expression implicitly convertible to the single argument
// of a one-argument T constructor.
// Converting constructions of optional<T> from optional<U> uses this function with
// 'Expr' being of type 'U' and relying on a converting constructor of T from U.
@ -441,7 +492,7 @@ class optional_base : public optional_tag
m_initialized = true ;
}
// Assigns using a form any expression implicitely convertible to the single argument
// Assigns using a form any expression implicitly convertible to the single argument
// of a T's assignment operator.
// Converting assignments of optional<T> from optional<U> uses this function with
// 'Expr' being of type 'U' and relying on a converting assignment of T from U.
@ -451,6 +502,8 @@ class optional_base : public optional_tag
assign_value(expr, is_reference_predicate());
}
#endif
#ifdef BOOST_OPTIONAL_WEAK_OVERLOAD_RESOLUTION
// BCB5.64 (and probably lower versions) workaround.
// The in-place factories are supported by means of catch-all constructors
@ -583,10 +636,7 @@ class optional : public optional_detail::optional_base<T>
#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
// Creates an optional<T> initialized with 'move(val)'.
// Can throw if T::T(T &&) does
optional ( rval_reference_type val ) BOOST_NOEXCEPT_IF(BOOST_NOEXCEPT_EXPR(T(static_cast<T&&>(val))))
:
base( static_cast<T&&>(val) )
{}
optional ( rval_reference_type val ) : base( boost::forward<T>(val) ) {}
#endif
// Creates an optional<T> initialized with 'val' IFF cond is true, otherwise creates an uninitialized optional.
@ -617,7 +667,7 @@ class optional : public optional_detail::optional_base<T>
base()
{
if ( rhs.is_initialized() )
this->construct( static_cast<BOOST_DEDUCED_TYPENAME optional<U>::rval_reference_type>(rhs.get()) );
this->construct( boost::move(rhs.get()) );
}
#endif
@ -625,32 +675,75 @@ class optional : public optional_detail::optional_base<T>
// Creates an optional<T> with an expression which can be either
// (a) An instance of InPlaceFactory (i.e. in_place(a,b,...,n);
// (b) An instance of TypedInPlaceFactory ( i.e. in_place<T>(a,b,...,n);
// (c) Any expression implicitely convertible to the single type
// (c) Any expression implicitly convertible to the single type
// of a one-argument T's constructor.
// (d*) Weak compilers (BCB) might also resolved Expr as optional<T> and optional<U>
// even though explicit overloads are present for these.
// Depending on the above some T ctor is called.
// Can throw is the resolved T ctor throws.
// Can throw if the resolved T ctor throws.
#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
#ifndef BOOST_NO_SFINAE
#else
template<class Expr>
explicit optional ( Expr&& expr, typename boost::disable_if<boost::is_same<typename boost::decay<Expr>::type, optional> >::type* = 0 )
: base(boost::forward<Expr>(expr),boost::addressof(expr)) {}
#endif
#else
template<class Expr>
explicit optional ( Expr const& expr ) : base(expr,boost::addressof(expr)) {}
#endif
#endif
// Creates a deep copy of another optional<T>
// Can throw if T::T(T const&) does
optional ( optional const& rhs ) : base( static_cast<base const&>(rhs) ) {}
#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
// Creates a deep move of another optional<T>
// Can throw if T::T(T&&) does
optional ( optional && rhs )
BOOST_NOEXCEPT_IF(::boost::is_nothrow_move_constructible<T>::value)
: base( boost::move(rhs) )
{}
#ifdef BOOST_NO_SFINAE
// To avoid too perfect forwarding
optional ( optional& rhs ) : base( static_cast<base const&>(rhs) ) {}
#endif
#endif
// No-throw (assuming T::~T() doesn't)
~optional() {}
#if !defined(BOOST_OPTIONAL_NO_INPLACE_FACTORY_SUPPORT) && !defined(BOOST_OPTIONAL_WEAK_OVERLOAD_RESOLUTION)
// Assigns from an expression. See corresponding constructor.
// Basic Guarantee: If the resolved T ctor throws, this is left UNINITIALIZED
#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
template<class Expr>
#if !defined BOOST_NO_SFINAE
typename boost::disable_if<
boost::is_same<typename boost::decay<Expr>::type, optional>,
optional&
>::type
#else
optional&
#endif
operator= ( Expr&& expr )
{
this->assign_expr(boost::forward<Expr>(expr),boost::addressof(expr));
return *this ;
}
#else
template<class Expr>
optional& operator= ( Expr const& expr )
{
this->assign_expr(expr,boost::addressof(expr));
return *this ;
}
#endif
#endif
// Assigns from another convertible optional<U> (converts && deep-copies the rhs value)
@ -675,11 +768,19 @@ class optional : public optional_detail::optional_base<T>
#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
// Assigns from another optional<T> (deep-moves the rhs value)
optional& operator= ( optional && rhs )
BOOST_NOEXCEPT_IF(BOOST_NOEXCEPT_EXPR(T(static_cast<optional &&>(*rhs))) && BOOST_NOEXCEPT_EXPR(*rhs = static_cast<optional &&>(*rhs)))
BOOST_NOEXCEPT_IF(::boost::is_nothrow_move_constructible<T>::value && ::boost::is_nothrow_move_assignable<T>::value)
{
this->assign( static_cast<optional &&>(rhs) ) ;
this->assign( static_cast<base &&>(rhs) ) ;
return *this ;
}
#ifdef BOOST_NO_SFINAE
// to avoid too perfect forwarding
optional& operator= ( optional& rhs )
{
this->assign( static_cast<base const&>(rhs) ) ;
return *this ;
}
#endif
#endif
// Assigns from a T (deep-copies the rhs value)
@ -694,7 +795,7 @@ class optional : public optional_detail::optional_base<T>
// Assigns from a T (deep-moves the rhs value)
optional& operator= ( rval_reference_type val )
{
this->assign( static_cast<rval_reference_type>(val) ) ;
this->assign( boost::move(val) ) ;
return *this ;
}
#endif
@ -709,7 +810,7 @@ class optional : public optional_detail::optional_base<T>
}
void swap( optional & arg )
BOOST_NOEXCEPT_IF(BOOST_NOEXCEPT_EXPR(T(static_cast<optional &&>(*arg))) && BOOST_NOEXCEPT_EXPR(*arg = static_cast<optional &&>(*arg)))
BOOST_NOEXCEPT_IF(::boost::is_nothrow_move_constructible<T>::value && ::boost::is_nothrow_move_assignable<T>::value)
{
// allow for Koenig lookup
boost::swap(*this, arg);
@ -740,11 +841,11 @@ class optional : public optional_detail::optional_base<T>
// implicit conversion to "bool"
// No-throw
operator unspecified_bool_type() const { return this->safe_bool() ; }
operator unspecified_bool_type() const BOOST_NOEXCEPT { return this->safe_bool() ; }
// This is provided for those compilers which don't like the conversion to bool
// on some contexts.
bool operator!() const { return !this->is_initialized() ; }
bool operator!() const BOOST_NOEXCEPT { return !this->is_initialized() ; }
} ;
// Returns optional<T>(v)
@ -1079,7 +1180,7 @@ template<class T>
struct optional_swap_should_use_default_constructor : has_nothrow_default_constructor<T> {} ;
template<class T> inline void swap ( optional<T>& x, optional<T>& y )
BOOST_NOEXCEPT_IF(BOOST_NOEXCEPT_EXPR(T(static_cast<optional &&>(*x))) && BOOST_NOEXCEPT_EXPR(*y = static_cast<optional &&>(*x)))
BOOST_NOEXCEPT_IF(::boost::is_nothrow_move_constructible<T>::value && ::boost::is_nothrow_move_assignable<T>::value)
{
optional_detail::swap_selector<optional_swap_should_use_default_constructor<T>::value>::optional_swap(x, y);
}

10
include/boost/optional/optional_fwd.hpp
View File

@ -11,15 +11,21 @@
//
// Revisions:
// 10 May 2008 (added swap related forward declaration) Niels Dekker
//
// 17 Apr 2014 (added noexcept) Andrzej Krzemienski
//
#ifndef BOOST_OPTIONAL_OPTIONAL_FWD_FLC_19NOV2002_HPP
#define BOOST_OPTIONAL_OPTIONAL_FWD_FLC_19NOV2002_HPP
#include <boost/config.hpp>
#include <boost/type_traits/is_nothrow_move_assignable.hpp>
#include <boost/type_traits/is_nothrow_move_constructible.hpp>
namespace boost {
template<class T> class optional ;
template<class T> void swap ( optional<T>& , optional<T>& ) ;
template<class T> void swap ( optional<T>& , optional<T>& )
BOOST_NOEXCEPT_IF(::boost::is_nothrow_move_constructible<T>::value && ::boost::is_nothrow_move_assignable<T>::value);
template<class T> struct optional_swap_should_use_default_constructor ;