Search results
Results From The WOW.Com Content Network
An object reference means a name, and the passed reference is an "alias", i.e. a copy of the reference to the same object, just as in C/C++. The object's value may be changed in the called function with the "alias", for example:
In that case a new object B is created, and the fields values of A are copied over to B. [3] [4] [5] This is also known as a field-by-field copy, [6] [7] [8] field-for-field copy, or field copy. [9] If the field value is a reference to an object (e.g., a memory address) it copies the reference, hence referring to the same object as A does, and ...
In C++, all non-reference class types have value semantics. In the above example, b is declared to be a reference (alias) of a, and for all purposes, a and b are the same thing. It is impossible to rebind b to become something else. After the above example is run, a and b are the same Foo object with prop being 3, while c is a copy of the ...
A Java example, when "copying" an object using simple assignment: Object original = new Object (); Object copy = null ; copy = original ; // does not copy object but only its reference The object is not duplicated, the variables 'original' and 'copy' are actually referring to the same object.
A copy constructor has a parameter of the same type passed as const reference, for example Vector(const Vector& rhs). If it is not provided explicitly, the compiler uses the copy constructor for each member variable or simply copies values in case of primitive types.
In computer programming, a weak reference is a reference that does not protect the referenced object from collection by a garbage collector, unlike a strong reference.An object referenced only by weak references – meaning "every chain of references that reaches the object includes at least one weak reference as a link" – is considered weakly reachable, and can be treated as unreachable and ...
In computer science, having value semantics (also value-type semantics or copy-by-value semantics) means for an object that only its value counts, not its identity. [1] [2] Immutable objects have value semantics trivially, [3] and in the presence of mutation, an object with value semantics can only be uniquely-referenced at any point in a program.
In a programming language, an evaluation strategy is a set of rules for evaluating expressions. [1] The term is often used to refer to the more specific notion of a parameter-passing strategy [2] that defines the kind of value that is passed to the function for each parameter (the binding strategy) [3] and whether to evaluate the parameters of a function call, and if so in what order (the ...