C++ concepts: MoveAssignable (since C++11)

 

C++

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C++ concepts

Basic
DefaultConstructible CopyAssignable CopyConstructible	MoveAssignable (C++11) MoveConstructible (C++11) Destructible
Library-Wide
EqualityComparable LessThanComparable Swappable (C++11) ValueSwappable (C++11)	NullablePointer (C++11) Hash (C++11) Allocator
Container
Container SequenceContainer ReversibleContainer	AssociativeContainer AllocatorAwareContainer UnorderedAssociativeContainer (C++11)
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CopyInsertable (C++11) MoveInsertable (C++11)	EmplaceConstructible (C++11)
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Iterator OutputIterator InputIterator	ForwardIterator BidirectionalIterator RandomAccessIterator
Stream I/O
FormattedInputFunction UnformattedInputFunction	FormattedOutputFunction UnformattedOutputFunction
Random Numbers
SeedSequence (C++11) RandomNumberEngine (C++11)	RandomNumberDistribution (C++11) UniformRandomNumberGenerator (C++11) RandomNumberEngineAdaptor (C++11)
Concurrency
BasicLockable (C++11) Lockable (C++11) TimedLockable (C++11)	Mutex (C++11) TimedMutex (C++11)
Other
CharTraits pos_type off_type Clock (C++11)	UnaryTypeTrait (C++11) BinaryTypeTrait (C++11) TransformationTrait (C++11) TrivialClock (C++11)

 

Specifies that an instance of the type can be move-assigned (moved). This means that type has move semantics: that is, can transfer its internal state to another instance of the same type potentially minimizing the overhead.

Requirements

The type must meet CopyAssignable requirements and/or implement the following functions:

Type::operator=

Type& Type::operator=( Type&& other ); Type& Type::operator=( const Type&& other ); Type& Type::operator=( volatile Type&& other ); Type& Type::operator=( const volatile Type&& other );		(One of the variants is sufficient)

Move assignment operator: assigns the contents of other. The internal state of other is unspecified after the move. However, it must still be valid, that is, no invariants of the type are broken. The function must return *this.

The following expressions must have the specified effects:

Expression	Effects
a = rv;	a is equivalent to rv, where a is an instance of Type and rv is a rvalue reference of Type.

See also

is_move_assignable is_trivially_move_assignable is_nothrow_move_assignable (C++11) (C++11) (C++11)	checks if a type has a move assignment operator (class template)