Concepts

From cppreference.com

C++ Reference
Language Concepts Utilities library Strings library Containers library Algorithms library Iterators library Numerics library Input/output library Localizations library Regular expressions library (C++11) Atomic operations library (C++11) Thread support library (C++11)
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) Container Elements CopyInsertable (C++11) MoveInsertable (C++11) EmplaceConstructible (C++11) Iterator Iterator OutputIterator InputIterator ForwardIterator BidirectionalIterator RandomAccessIterator 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)

Concept is a term that describes a set of characteristics of a type. Concepts are a more convenient way to specify both what properties are expected from a type, and what properties a type has.

There was a proposal to include formal specification of concepts into the C++ language, so that the compiler could check the type requirements before template instantiation and in turn could produce much more sensible error messages in case a type did not fulfill the template requirements. This proposal was later dropped for various reasons. However, there are unofficial plans to add concepts to a future revision of the C++ language.

Contents 1 Basic 2 Library-wide 3 Container 3.1 Container element 4 Iterator 5 Random Number Generation 6 Concurrency 7 Other Basic
DefaultConstructible	specifies that type has default constructor (concept)
MoveConstructible (C++11)	specifies that type has move constructor (concept)
CopyConstructible	specifies that type has copy constructor (concept)
MoveAssignable (C++11)	specifies that type can move assignment operator (concept)
CopyAssignable	specifies that type has copy assignment operator (concept)
Destructible	type has a destructor that clears all memory (concept)
Library-wide
EqualityComparable	has a working operator== that is an equivalence relation (concept)
LessThanComparable	operator< is a strict weak ordering relation (concept)
Swappable (C++11)	can be used as argument of std::swap (concept)
ValueSwappable (C++11)	Pointer-like type that when dereferenced can be passed to std::swap (concept)
NullablePointer (C++11)	Pointer-like type supporting a null value (concept)
Hash (C++11)	(concept)
Allocator	Class type that contains allocation information (concept)
Container
Container	data structure that allows element access using iterators (concept)
ReversibleContainer	container using bidirectional iterators (concept)
AllocatorAwareContainer (C++11)	container using an allocator (concept)
SequenceContainer	container with elements stored linearly (concept)
AssociativeContainer	container that stores elements by associating them to keys (concept)
UnorderedAssociativeContainer (C++11)	container that stores elements stored in buckets by associating them to keys (concept)
Container element
CopyInsertable (C++11)	(concept)
MoveInsertable (C++11)	(concept)
EmplaceConstructible (C++11)	(concept)
Iterator
Iterator	general concept to access data within some data structure (concept)
InputIterator	iterator that can be used to read data (concept)
OutputIterator	iterator that can be used to write data (concept)
ForwardIterator	iterator that can be used to read data multiple times (concept)
BidirectionalIterator	iterator that can be both incremented and decremented (concept)
RandomAccessIterator	iterator that can be advanced in constant time (concept)
Random Number Generation
SeedSequence (C++11)	(concept)
UniformRandomNumberGenerator (C++11)	(concept)
RandomNumberEngine (C++11)	(concept)
RandomNumberEngineAdaptor (C++11)	(concept)
RandomNumberDistribution (C++11)	(concept)
Concurrency
BasicLockable (C++11)	(concept)
Lockable (C++11)	(concept)
TimedLockable (C++11)	(concept)
Mutex (C++11)	(concept)
TimedMutex (C++11)	(concept)
Other
UnaryTypeTrait (C++11)	(concept)
BinaryTypeTrait (C++11)	(concept)
TransformationTrait (C++11)	(concept)
Clock (C++11)	(concept)
TrivialClock (C++11)	(concept)
CharTraits	(concept)
pos_type	(concept)
off_type	(concept)

This section is incomplete Reason: Any other missing concept?