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-rw-r--r--boost/optional/optional.hpp117
1 files changed, 71 insertions, 46 deletions
diff --git a/boost/optional/optional.hpp b/boost/optional/optional.hpp
index 07c4bd39ab..afcb8079e2 100644
--- a/boost/optional/optional.hpp
+++ b/boost/optional/optional.hpp
@@ -1,5 +1,5 @@
// Copyright (C) 2003, 2008 Fernando Luis Cacciola Carballal.
-// Copyright (C) 2014 Andrzej Krzemienski.
+// Copyright (C) 2014, 2015 Andrzej Krzemienski.
//
// Use, modification, and distribution is subject to the Boost Software
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
@@ -57,6 +57,10 @@
#include <boost/optional/optional_fwd.hpp>
+#if (defined BOOST_NO_CXX11_RVALUE_REFERENCES) || (defined BOOST_OPTIONAL_CONFIG_NO_RVALUE_REFERENCES)
+#define BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
+#endif
+
#if BOOST_WORKAROUND(BOOST_INTEL_CXX_VERSION,<=700)
// AFAICT only Intel 7 correctly resolves the overload set
// that includes the in-place factory taking functions,
@@ -148,7 +152,7 @@ struct types_when_isnt_ref
{
typedef T const& reference_const_type ;
typedef T & reference_type ;
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
typedef T && rval_reference_type ;
typedef T && reference_type_of_temporary_wrapper;
#ifdef BOOST_MOVE_OLD_RVALUE_REF_BINDING_RULES
@@ -171,7 +175,7 @@ struct types_when_is_ref
typedef raw_type& reference_const_type ;
typedef raw_type& reference_type ;
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
typedef BOOST_DEDUCED_TYPENAME remove_const<raw_type>::type&& rval_reference_type ;
typedef raw_type& reference_type_of_temporary_wrapper;
static reference_type move(reference_type r) { return r; }
@@ -184,7 +188,7 @@ struct types_when_is_ref
template <class To, class From>
void prevent_binding_rvalue_ref_to_optional_lvalue_ref()
{
-#ifndef BOOST_OPTIONAL_ALLOW_BINDING_TO_RVALUES
+#ifndef BOOST_OPTIONAL_CONFIG_ALLOW_BINDING_TO_RVALUES
BOOST_STATIC_ASSERT_MSG(
!boost::is_lvalue_reference<To>::value || !boost::is_rvalue_reference<From>::value,
"binding rvalue references to optional lvalue references is disallowed");
@@ -226,7 +230,7 @@ class optional_base : public optional_tag
protected:
typedef BOOST_DEDUCED_TYPENAME types::reference_type reference_type ;
typedef BOOST_DEDUCED_TYPENAME types::reference_const_type reference_const_type ;
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
typedef BOOST_DEDUCED_TYPENAME types::rval_reference_type rval_reference_type ;
typedef BOOST_DEDUCED_TYPENAME types::reference_type_of_temporary_wrapper reference_type_of_temporary_wrapper ;
#endif
@@ -255,7 +259,7 @@ class optional_base : public optional_tag
construct(val);
}
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
// move-construct an optional<T> initialized from an rvalue-ref to 'val'.
// Can throw if T::T(T&&) does
optional_base ( rval_reference_type val )
@@ -286,7 +290,7 @@ class optional_base : public optional_tag
construct(rhs.get_impl());
}
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
// Creates a deep move of another optional<T>
// Can throw if T::T(T&&) does
optional_base ( optional_base&& rhs )
@@ -298,7 +302,7 @@ class optional_base : public optional_tag
}
#endif
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
template<class Expr, class PtrExpr>
explicit optional_base ( Expr&& expr, PtrExpr const* tag )
@@ -342,7 +346,7 @@ class optional_base : public optional_tag
}
}
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
// Assigns from another optional<T> (deep-moves the rhs value)
void assign ( optional_base&& rhs )
{
@@ -367,17 +371,26 @@ class optional_base : public optional_tag
if (is_initialized())
{
if ( rhs.is_initialized() )
- assign_value(static_cast<value_type>(rhs.get()), is_reference_predicate() );
+#ifndef BOOST_OPTIONAL_CONFIG_RESTORE_ASSIGNMENT_OF_NONCONVERTIBLE_TYPES
+ assign_value(rhs.get(), is_reference_predicate() );
+#else
+ assign_value(static_cast<value_type>(rhs.get()), is_reference_predicate() );
+#endif
+
else destroy();
}
else
{
if ( rhs.is_initialized() )
+#ifndef BOOST_OPTIONAL_CONFIG_RESTORE_ASSIGNMENT_OF_NONCONVERTIBLE_TYPES
+ construct(rhs.get());
+#else
construct(static_cast<value_type>(rhs.get()));
+#endif
}
}
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
// move-assigns from another _convertible_ optional<U> (deep-moves from the rhs value)
template<class U>
void assign ( optional<U>&& rhs )
@@ -405,7 +418,7 @@ class optional_base : public optional_tag
else construct(val);
}
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
// Assigns from a T (deep-moves the rhs value)
void assign ( rval_reference_type val )
{
@@ -421,7 +434,7 @@ class optional_base : public optional_tag
#ifndef BOOST_OPTIONAL_NO_INPLACE_FACTORY_SUPPORT
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
template<class Expr, class ExprPtr>
void assign_expr ( Expr&& expr, ExprPtr const* tag )
{
@@ -466,7 +479,7 @@ class optional_base : public optional_tag
m_initialized = true ;
}
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
void construct ( rval_reference_type val )
{
::new (m_storage.address()) internal_type( types::move(val) ) ;
@@ -475,7 +488,7 @@ class optional_base : public optional_tag
#endif
-#if (!defined BOOST_NO_CXX11_RVALUE_REFERENCES) && (!defined BOOST_NO_CXX11_VARIADIC_TEMPLATES)
+#if (!defined BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES) && (!defined BOOST_NO_CXX11_VARIADIC_TEMPLATES)
// Constructs in-place
// upon exception *this is always uninitialized
template<class... Args>
@@ -485,7 +498,7 @@ class optional_base : public optional_tag
::new (m_storage.address()) internal_type( boost::forward<Args>(args)... );
m_initialized = true ;
}
-#elif (!defined BOOST_NO_CXX11_RVALUE_REFERENCES)
+#elif (!defined BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES)
template<class Arg>
void emplace_assign ( Arg&& arg )
{
@@ -513,7 +526,7 @@ class optional_base : public optional_tag
#ifndef BOOST_OPTIONAL_NO_INPLACE_FACTORY_SUPPORT
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
// Constructs in-place using the given factory
template<class Expr>
void construct ( Expr&& factory, in_place_factory_base const* )
@@ -584,7 +597,7 @@ class optional_base : public optional_tag
#endif
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+#ifndef BOOST_OPTIONAL_DETAIL_NO_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
@@ -642,7 +655,7 @@ class optional_base : public optional_tag
// For VC<=70 compilers this workaround dosen't work becasue the comnpiler issues and error
// instead of choosing the wrong overload
//
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
// Notice that 'Expr' will be optional<T> or optional<U> (but not optional_base<..>)
template<class Expr>
void construct ( Expr&& expr, optional_tag const* )
@@ -673,7 +686,7 @@ class optional_base : public optional_tag
void assign_value ( argument_type val, is_not_reference_tag ) { get_impl() = val; }
void assign_value ( argument_type val, is_reference_tag ) { construct(val); }
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
void assign_value ( rval_reference_type val, is_not_reference_tag ) { get_impl() = static_cast<rval_reference_type>(val); }
void assign_value ( rval_reference_type val, is_reference_tag ) { construct( static_cast<rval_reference_type>(val) ); }
#endif
@@ -750,7 +763,7 @@ class optional : public optional_detail::optional_base<T>
typedef BOOST_DEDUCED_TYPENAME base::value_type value_type ;
typedef BOOST_DEDUCED_TYPENAME base::reference_type reference_type ;
typedef BOOST_DEDUCED_TYPENAME base::reference_const_type reference_const_type ;
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
typedef BOOST_DEDUCED_TYPENAME base::rval_reference_type rval_reference_type ;
typedef BOOST_DEDUCED_TYPENAME base::reference_type_of_temporary_wrapper reference_type_of_temporary_wrapper ;
#endif
@@ -770,7 +783,7 @@ class optional : public optional_detail::optional_base<T>
// Can throw if T::T(T const&) does
optional ( argument_type val ) : base(val) {}
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
// Creates an optional<T> initialized with 'move(val)'.
// Can throw if T::T(T &&) does
optional ( rval_reference_type val ) : base( boost::forward<T>(val) )
@@ -795,7 +808,7 @@ class optional : public optional_detail::optional_base<T>
this->construct(rhs.get());
}
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
// Creates a deep move of another convertible optional<U>
// Requires a valid conversion from U to T.
// Can throw if T::T(U&&) does
@@ -819,7 +832,7 @@ class optional : public optional_detail::optional_base<T>
// even though explicit overloads are present for these.
// Depending on the above some T ctor is called.
// Can throw if the resolved T ctor throws.
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
template<class Expr>
@@ -834,14 +847,14 @@ class optional : public optional_detail::optional_base<T>
#else
template<class Expr>
explicit optional ( Expr const& expr ) : base(expr,boost::addressof(expr)) {}
-#endif // !defined BOOST_NO_CXX11_RVALUE_REFERENCES
+#endif // !defined BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
#endif // !defined BOOST_OPTIONAL_NO_INPLACE_FACTORY_SUPPORT
// 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
+#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
// Creates a deep move of another optional<T>
// Can throw if T::T(T&&) does
optional ( optional && rhs )
@@ -856,7 +869,7 @@ class optional : public optional_detail::optional_base<T>
#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
+#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
template<class Expr>
BOOST_DEDUCED_TYPENAME boost::disable_if_c<
@@ -878,7 +891,7 @@ class optional : public optional_detail::optional_base<T>
this->assign_expr(expr,boost::addressof(expr));
return *this ;
}
-#endif // !defined BOOST_NO_CXX11_RVALUE_REFERENCES
+#endif // !defined BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
#endif // !defined(BOOST_OPTIONAL_NO_INPLACE_FACTORY_SUPPORT) && !defined(BOOST_OPTIONAL_WEAK_OVERLOAD_RESOLUTION)
// Copy-assigns from another convertible optional<U> (converts && deep-copies the rhs value)
@@ -891,7 +904,7 @@ class optional : public optional_detail::optional_base<T>
return *this ;
}
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
// Move-assigns from another convertible optional<U> (converts && deep-moves the rhs value)
// Requires a valid conversion from U to T.
// Basic Guarantee: If T::T( U && ) throws, this is left UNINITIALIZED
@@ -912,7 +925,7 @@ class optional : public optional_detail::optional_base<T>
return *this ;
}
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
// Assigns from another optional<T> (deep-moves the rhs value)
optional& operator= ( optional && rhs )
BOOST_NOEXCEPT_IF(::boost::is_nothrow_move_constructible<T>::value && ::boost::is_nothrow_move_assignable<T>::value)
@@ -930,7 +943,7 @@ class optional : public optional_detail::optional_base<T>
return *this ;
}
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
// Assigns from a T (deep-moves the rhs value)
optional& operator= ( rval_reference_type val )
{
@@ -949,7 +962,7 @@ class optional : public optional_detail::optional_base<T>
return *this ;
}
-#if (!defined BOOST_NO_CXX11_RVALUE_REFERENCES) && (!defined BOOST_NO_CXX11_VARIADIC_TEMPLATES)
+#if (!defined BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES) && (!defined BOOST_NO_CXX11_VARIADIC_TEMPLATES)
// Constructs in-place
// upon exception *this is always uninitialized
template<class... Args>
@@ -957,7 +970,7 @@ class optional : public optional_detail::optional_base<T>
{
this->emplace_assign( boost::forward<Args>(args)... );
}
-#elif (!defined BOOST_NO_CXX11_RVALUE_REFERENCES)
+#elif (!defined BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES)
template<class Arg>
void emplace ( Arg&& arg )
{
@@ -1004,16 +1017,16 @@ class optional : public optional_detail::optional_base<T>
// Returns a reference to the value if this is initialized, otherwise,
// the behaviour is UNDEFINED
// No-throw
-#ifndef BOOST_NO_CXX11_REF_QUALIFIERS
+#if (!defined BOOST_NO_CXX11_REF_QUALIFIERS) && (!defined BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES)
reference_const_type operator *() const& { return this->get() ; }
reference_type operator *() & { return this->get() ; }
- reference_type_of_temporary_wrapper operator *() && { return boost::move(this->get()) ; }
+ reference_type_of_temporary_wrapper operator *() && { return base::types::move(this->get()) ; }
#else
reference_const_type operator *() const { return this->get() ; }
reference_type operator *() { return this->get() ; }
#endif // !defined BOOST_NO_CXX11_REF_QUALIFIERS
-#ifndef BOOST_NO_CXX11_REF_QUALIFIERS
+#if (!defined BOOST_NO_CXX11_REF_QUALIFIERS) && (!defined BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES)
reference_const_type value() const&
{
if (this->is_initialized())
@@ -1033,7 +1046,7 @@ class optional : public optional_detail::optional_base<T>
reference_type_of_temporary_wrapper value() &&
{
if (this->is_initialized())
- return boost::move(this->get()) ;
+ return base::types::move(this->get()) ;
else
throw_exception(bad_optional_access());
}
@@ -1071,11 +1084,11 @@ class optional : public optional_detail::optional_base<T>
value_type value_or ( U&& v ) &&
{
if (this->is_initialized())
- return boost::move(get());
+ return base::types::move(get());
else
return boost::forward<U>(v);
}
-#elif !defined BOOST_NO_CXX11_RVALUE_REFERENCES
+#elif !defined BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
template <class U>
value_type value_or ( U&& v ) const
{
@@ -1093,6 +1106,15 @@ class optional : public optional_detail::optional_base<T>
else
return v;
}
+
+ template <class U>
+ value_type value_or ( U& v ) const
+ {
+ if (this->is_initialized())
+ return get();
+ else
+ return v;
+ }
#endif
@@ -1110,7 +1132,7 @@ class optional : public optional_detail::optional_base<T>
value_type value_or_eval ( F f ) &&
{
if (this->is_initialized())
- return boost::move(get());
+ return base::types::move(get());
else
return f();
}
@@ -1130,7 +1152,7 @@ class optional : public optional_detail::optional_base<T>
BOOST_EXPLICIT_OPERATOR_BOOL_NOEXCEPT()
} ;
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
template<class T>
class optional<T&&>
{
@@ -1226,10 +1248,13 @@ get_pointer ( optional<T>& opt )
return opt.get_ptr() ;
}
-// Forward declaration to prevent operator safe-bool from being used.
-template<class CharType, class CharTrait, class T>
+// The following declaration prevents a bug where operator safe-bool is used upon streaming optional object if you forget the IO header.
+template<class CharType, class CharTrait>
std::basic_ostream<CharType, CharTrait>&
-operator<<(std::basic_ostream<CharType, CharTrait>& out, optional<T> const& v);
+operator<<(std::basic_ostream<CharType, CharTrait>& out, optional_detail::optional_tag const& v)
+{
+ BOOST_STATIC_ASSERT_MSG(sizeof(CharType) == 0, "If you want to output boost::optional, include header <boost/optional/optional_io.hpp>");
+}
// optional's relational operators ( ==, !=, <, >, <=, >= ) have deep-semantics (compare values).
// WARNING: This is UNLIKE pointers. Use equal_pointees()/less_pointess() in generic code instead.
@@ -1437,7 +1462,7 @@ struct swap_selector<true>
}
};
-#ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
+#ifndef BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
template<>
struct swap_selector<false>
{
@@ -1494,7 +1519,7 @@ struct swap_selector<false>
}
}
};
-#endif // !defined BOOST_NO_CXX11_RVALUE_REFERENCES
+#endif // !defined BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
} // namespace optional_detail