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Instead, the name of the parent or base class is used followed by the scope resolution operator. For example, the following code presents two classes, the base class Rectangle, and the derived class Box. Box overrides the Rectangle class's Print method, so as also to print its height. [7]
In computer programming, scope is an enclosing context where values and expressions are associated. The scope resolution operator helps to identify and specify the context to which an identifier refers, particularly by specifying a namespace or class. The specific uses vary across different programming languages with the notions of scoping.
If a function is declared in one scope, and then another function with the same name is declared in an inner scope, there are two natural possible overloading behaviors: the inner declaration masks the outer declaration (regardless of signature), or both the inner declaration and the outer declaration are included in the overload, with the ...
Scope is an important component of name resolution, [d] which is in turn fundamental to language semantics. Name resolution (including scope) varies between programming languages, and within a programming language, varies by type of entity; the rules for scope are called scope rules (or scoping rules).
The C# language breaks this tradition, allowing variable shadowing between an inner and an outer class, and between a method and its containing class, but not between an if-block and its containing method, or between case statements in a switch block. Some languages allow variable shadowing in more cases than others.
A somewhat common misconception is that dynamic typing implies dynamic name resolution. For example, Erlang is dynamically typed but has static name resolution. However, static typing does imply static name resolution. Static name resolution catches, at compile time, use of variables that are not in scope; preventing programmer errors.
The term closure is often used as a synonym for anonymous function, though strictly, an anonymous function is a function literal without a name, while a closure is an instance of a function, a value, whose non-local variables have been bound either to values or to storage locations (depending on the language; see the lexical environment section below).
C# has explicit support for covariance and contravariance in generic types, [16]: 144 [20]: 23 unlike C++ which has some degree of support for contravariance simply through the semantics of return types on virtual methods. Enumeration members are placed in their own scope. The C# language does not allow for global variables or functions.