Descending precedence refers to the priority of the grouping of operators and operands. Operators are listed top to bottom, in descending precedence. The following is a table that lists the precedence and associativity of all the operators in the C and C++ languages. ^ C++ defines alignof operator, whereas C defines _Alignof.However, they are usually used regardless. ^ The parentheses are not necessary when taking the size of a value, only when taking the size of a type.^ Meyers, Scott (October 1999), "Implementing operator->* for Smart Pointers" (PDF), Dr.If x is of type C where C overloads operator -> (), x -> y gets expanded to x. ^ The return type of operator -> () must be a type for which the -> operation can be applied, such as a pointer type.Most implementations, e.g., the GCC, use an arithmetic shift (i.e., sign extension), but a logical shift is possible. ^ a b According to the C99 standard, the right shift of a negative number is implementation defined.^ a b In the context of iostreams, writers often will refer to > as the "put-to" or "stream insertion" and "get-from" or "stream extraction" operators, respectively.^ a b c d e f g h i j k Requires iso646.h in C.^ The modulus operator works just with integer operands, for floating point numbers a library function must be used instead (like fmod ).Note: for user-defined conversions, the return type implicitly and necessarily matches the operator name. Note: behaves like const_cast/static_cast/reinterpret_cast Member of object a selected by pointer-to-member b Member selected by pointer-to-member b of object pointed to by a
Structure reference ("member b of object a") Structure dereference ("member b of object pointed to by a") Member and pointer operators Operator name Operator nameĪll bitwise operators exist in C and C++ and can be overloaded in C++.Īll assignment expressions exist in C and C++ and can be overloaded in C++.įor the given operators the semantic of the built-in combined assignment expression a ⊚= b is equivalent to a = a ⊚ b, except that a is evaluated only once. The operator has a total of 3 possible return types: std::weak_ordering, std::strong_ordering and std::partial_ordering to which they all are convertible to.Īll logical operators exist in C and C++ and can be overloaded in C++, albeit the overloading of the logical AND and logical OR is discouraged, because as overloaded operators they behave as ordinary function calls, which means that both of their operands are evaluated, so they lose their well-used and expected short-circuit evaluation property. Note: C++ uses the unnamed dummy-parameter int to differentiate between prefix and postfix decrement operators.Ĭomparison operators/relational operators Īll comparison operators can be overloaded in C++.īool K :: operator = ( S const & b ) const īool operator = ( K const & a, S const & b ) īool K :: operator != ( S const & b ) const īool operator != ( K const & a, S const & b ) īool K :: operator > ( S const & b ) const īool operator > ( K const & a, S const & b ) īool K :: operator >= ( S const & b ) const īool operator >= ( K const & a, S const & b ) Īuto operator ( const K & a, const S & b ) Note: C++ uses the unnamed dummy-parameter int to differentiate between prefix and postfix increment operators. R, S and T stand for any type(s), and K for a class type or enumerated type.Īll arithmetic operators exist in C and C++ and can be overloaded in C++. 2.2 Criticism of bitwise and equality operators precedenceįor the purposes of these tables, a, b, and c represent valid values (literals, values from variables, or return value), object names, or lvalues, as appropriate.1.2 Comparison operators/relational operators.
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