assignment-operator

When is overloading pass by reference (l-value and r-value) preferred to pass-by-value?

For types whose copy assignment operator can recycle resources, swapping with a copy is almost never the best way to implement the copy assignment operator. For example look at std::vector: This class manages a dynamically sized buffer and maintains both a capacity (maximum length the buffer can hold), and a size (the current length). If … Read more

Why doesn’t Java have compound assignment versions of the conditional-and and conditional-or operators? (&&=, ||=)

Reason The operators &&= and ||= are not available on Java because for most of the developers these operators are: error-prone useless Example for &&= If Java allowed &&= operator, then that code: bool isOk = true; //becomes false when at least a function returns false isOK &&= f1(); isOK &&= f2(); //we may expect … Read more

Scalar vs List Assignment Operator

The symbol = is compiled into one of two assignment operators: A list assignment operator (aassign) is used if the left-hand side (LHS) of a = is some kind of aggregate. A scalar assignment operator (sassign) is used otherwise. The following are considered to be aggregates: Any expression in parentheses (e.g. (…)) An array (e.g. … Read more

How to use base class’s constructors and assignment operator in C++?

You can explicitly call constructors and assignment operators: class Base { //… public: Base(const Base&) { /*…*/ } Base& operator=(const Base&) { /*…*/ } }; class Derived : public Base { int additional_; public: Derived(const Derived& d) : Base(d) // dispatch to base copy constructor , additional_(d.additional_) { } Derived& operator=(const Derived& d) { Base::operator=(d); … Read more