Comparison operators

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Compares the arguments.

Operator name	Syntax	Overloadable	Prototype examples (for class T)
Operator name	Syntax	Overloadable	Inside class definition	Outside class definition
equal to	`a == b`	Yes	bool T::operator ==(const T2 &b) const;	bool operator ==(const T &a, const T2 &b);
not equal to	`a != b`	Yes	bool T::operator !=(const T2 &b) const;	bool operator !=(const T &a, const T2 &b);
less than	`a < b`	Yes	bool T::operator <(const T2 &b) const;	bool operator <(const T &a, const T2 &b);
greater than	`a > b`	Yes	bool T::operator >(const T2 &b) const;	bool operator >(const T &a, const T2 &b);
less than or equal to	`a <= b`	Yes	bool T::operator <=(const T2 &b) const;	bool operator <=(const T &a, const T2 &b);
greater than or equal to	`a >= b`	Yes	bool T::operator >=(const T2 &b) const;	bool operator >=(const T &a, const T2 &b);
Notes All operators usually return a value of type T. However, essentially any type can be returned (including void, i.e. no return value), yet this is unintuitive and thus defeats the purpose of the operators. `T2` can be any type including `T`

Returns the result of comparison of the value of the arguments. They are not modified.

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 (since C++11) `typeid` queries the type information of a type `noexcept` checks if an expression can throw an exception (since C++11) `alignof` queries alignment requirements of a type (since C++11)