Comparison operators

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Accesses a member of an object.

Operator name	Syntax	Overloadable	Prototype examples (for class T)
Operator name	Syntax	Overloadable	Inside class definition	Outside class definition
array subscript	`a[b]`	Yes	R T::operator[](const T2 &b);	N/A
indirection (variable pointed to by `a`)	`*a`	Yes	R& T::operator*();	R& operator(T &a);
address of	`&a`	Yes	R* T::operator&();	R* operator&(T &a);
member of object	`a.b`	No	N/A	N/A
member of pointer	`a->b`	Yes	R* T::operator->()	N/A
pointer to member of object	`a.*b`	No	N/A	N/A
member of pointer	`a->b`	Yes	R* T::operator->*(R)	R* T::operator->*(T, R)
Notes The return type R can essentially be any type. However, some some operators are expected to return specific types, e.g. indirection operator is expected to return reference type. If other types are returned, the operator operation becomes unintuitive and thus defeats the purpose of the operators.

array subscript operator provides access to the elements in the internal array

indirection, member of pointer and pointer to member of pointer operators provide provide pointer semantics for any object.

member of pointer and pointer to member of pointer operators return a pointer to the actual object which will be used for member access.

Common operators
assignment	increment decrement	arithmetic	logical	comparison	member access	other
a = b a = rvalue a += b a -= b a *= b a /= b a %= b a &= b a \|= b a ^= b a <<= b a >>= b	++a --a a++ a--	+a -a a + b a - b a * b a / b a % b ~a a & b a \| b a ^ b a << b a >> b	!a a && b a \|\| b	a == b a != b a < b a > b a <= b a >= b	a[b] a &a a->b a.b a->b a.*b	a(...) a, b (type) a ? :
Special operators
`static_cast` converts one type to another compatible type `dynamic_cast` converts virtual base class to derived class `const_cast` converts type to compatible type with different cv qualifiers `reinterpret_cast` converts type to incompatible type `new` allocates memory `delete` deallocates memory `sizeof` queries the size of a type `sizeof...` queries the size of a parameter pack (C++11 feature) `typeid` queries the type information of a type `noexcept` checks if an expression can throw an exception (C++11 feature) `alignof` queries alignment requirements of a type (C++11 feature)