Name Binding - Binding Time

Binding Time

The binding of names before the program is run is called static (also "early"); bindings performed as the program runs are dynamic (also "late" or "virtual").

An example of a static binding is a direct C function call: the function referenced by the identifier cannot change at runtime.

But an example of dynamic binding is dynamic dispatch, as in a C++ virtual method call. Since the specific type of a polymorphic object is not known before runtime (in general), the executed function is dynamically bound. Take, for example, the following Java code:

public void foo(java.util.List list) { list.add("bar"); }

List is an interface, so list must refer to a subtype of it. Is it a reference to a LinkedList, an ArrayList, or some other subtype of List? The actual method referenced by add is not known until runtime. In a language like C, the actual function is known.

Read more about this topic:  Name Binding

Famous quotes containing the words binding and/or time:

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    —Alan Jay Lerner (1918–1986)

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    —Dylan Thomas (1914–1953)