c++oggetti

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Operator name Syntax Overloadable Included

in C

Basic assignment a = b Yes Yes

Addition a + b Yes Yes

Subtraction a - b Yes Yes

Unary plus (integer

promotion)

+a Yes Yes

Unary minus

(additive inverse)

-a Yes Yes

Multiplication a * b Yes Yes

Division a / b Yes Yes

Modulo (remainder) a % b Yes Yes

Increment Prefix ++a Yes Yes

Suffix a++ Yes Yes

Decrement Prefix --a Yes Yes

Suffix a-- Yes Yes

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Prototype examples (T is any type)

As member of T Outside class definitions

T& T::operator =(const T& b); N/A

T T::operator +(const T& b) const; T operator +(const T& a, const T& b);

T T::operator -(const T& b) const; T operator -(const T& a, const T& b);

T T::operator +() const; T operator +(const T& a);

T T::operator -() const; T operator -(const T& a);

T T::operator *(const T& b) const; T operator *(const T &a, const T& b);

T T::operator /(const T& b) const; T operator /(const T& a, const T& b);

T T::operator %(const T& b) const; T operator %(const T& a, const T& b);

T& T::operator ++(); T& operator ++(T& a);

T T::operator ++(int); T operator ++(T& a, int);

Note: C++ uses the unnamed dummy-parameter int to

differentiate between prefix and Suffix increment operators.

T& T::operator --(); T& operator --(T& a);T T::operator --(int); T operator --(T& a, int);

Note: C++ uses the unnamed dummy-parameter int to

differentiate between prefix and Suffix decrement operators.

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in C

Equal to a == b Yes Yes

Not equal to a != b Yes Yes

Greater than a > b Yes Yes

Less than a < b Yes Yes

Greater than or equal to a >= b Yes Yes

Less than or equal to a

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As member of T

bool T::operator ==(const T& b) const;

bool T::operator !=(const T& b) const;

bool T::operator >(const T& b) const;

bool T::operator =(const T& b) const;

bool T::operator

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Outside class definitions

bool operator ==(const T& a, const T& b);

bool operator !=(const T& a, const T& b);

bool operator >(const T& a, const T& b);

bool operator =(const T& a, const T& b);

bool operator

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in C

Logical negation (NOT) !a Yes Yes

Logical AND a && b Yes Yes

Logical OR a || b Yes Yes

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As member of T

bool T::operator !() const;

bool T::operator &&(const T& b) const;

bool T::operator ||(const T& b) const;

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bool operator !(const T& a);

bool operator &&(const T& a, const T& b);

bool operator ||(const T& a, const T& b);

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in C

Bitwise NOT ~a Yes Yes

Bitwise AND a & b Yes Yes

Bitwise OR a | b Yes Yes

Bitwise XOR a ^ b Yes Yes

Bitwise left shift[note 1] a > b Yes Yes

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As member of T

T T::operator ~() const;

T T::operator &(const T& b) const;

T T::operator |(const T& b) const;

T T::operator ^(const T& b) const;

T T::operator (const T& b) const;

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T operator ~(const T& a);

T operator &(const T& a, const T& b);

T operator |(const T& a, const T& b);

T operator ^(const T& a, const T& b);

T operator (const T& a, const T& b);

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in C

Addition assignment a += b Yes Yes

Subtraction assignment a -= b Yes Yes

Multiplication assignment a *= b Yes Yes

Division assignment a /= b Yes Yes

Modulo assignment a %= b Yes Yes

Bitwise AND assignment a &= b Yes Yes

Bitwise OR assignment a |= b Yes Yes

Bitwise XOR assignment a ^= b Yes Yes

Bitwise left shift assignment a = b Yes Yes

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T& T::operator +=(const T& b); T& operator +=(T& a, const T& b);

T& T::operator -=(const T& b); T& operator -=(T& a, const T& b);

T& T::operator *=(const T& b); T& operator *=(T& a, const T& b);

T& T::operator /=(const T& b); T& operator /=(T& a, const T& b);

T& T::operator %=(const T& b); T& operator %=(T& a, const T& b);

T& T::operator &=(const T& b); T& operator &=(T& a, const T& b);

T& T::operator |=(const T& b); T& operator |=(T& a, const T& b);

T& T::operator ^=(const T& b); T& operator ^=(T& a, const T& b);

T& T::operator =(T& a, const T& b);

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in C

Array subscript a[b] Yes Yes

Indirection ("variable pointed to by a") *a Yes Yes

Reference ("address of a") &a Yes Yes

Member b of object pointed to by a a->b Yes Yes

Member b of object a a.b No Yes

Member pointed to by b of object pointed to by a, a->*b Yes No

Member pointed to by b of object a a.*b No No

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Prototype examples


R& T::operator [](const T2& b); N/A

R& T::operator *(); R& operator *(T& a);

T* T::operator &(); T* operator &(T& a);

T2* T::operator ->(); N/A

N/A

R T::operator->*(T2); R operator->*(T, T2);

N/A

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in C

Function call

See Function object.

a(a1, a2) Yes Yes

Comma a, b Yes Yes

Ternary conditional a ? b : c No Yes

Scope resolution a::b No No

Size-of sizeof(a)

sizeof(type)

No Yes

Type identification typeid(a)

typeid(type)

No No

Cast (type) a Yes Yes

Allocate storage new type Yes No

Allocate storage (array) new type[n] Yes No

Deallocate storage delete a Yes NoDeallocate storage (array) delete[] a Yes No

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Prototype examples


R T::operator ()(Arg1 a1, Arg2 a2, ); N/A

T2& T::operator ,(T2& b) const; T2& operator ,(const T& a, T2& b);

N/A

N/A

N/A

N/A

T::operator T2() const; N/A

Note: for user-defined conversions, the return type implicitly and

necessarily matches the operator name.

void* T::operator new(size_t x); void* operator new(size_t x);

void* T::operator new[](size_t x); void* operator new[](size_t x);

void T::operator delete(void* x); void operator delete(void* x);void T::operator delete[](void* x); void operator delete[](void* x);

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