Binding (computer science)

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In computer science, binding is the creation of a simple reference to something that is larger and more complicated and used frequently. The simple reference can be used instead of having to repeat the larger thing. A binding is such a reference.[citation needed]

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[edit] Types of binding

The following are commonly referred to as bindings.

[edit] Language or Name binding

Main articles: Name binding and Language binding

The terms language binding and name binding refer to both the linking of libraries to application programs, and to the way symbols (variable names) are handled by compilers.

In programming languages, these terms mean the references of an identifier to a value. In this context, binding is the act of associating a name or symbol with a machine address, and this association may occur either at compile time, in which case it is called 'static linking', or it may occur dynamically at runtime, which is called 'dynamic linking'. The terms binding and linking are used interchangeably in some contexts.

Static binding has an additional characteristic: it prevents libraries from being updated (recompiled) independently of applications.

[edit] XML data binding

Main article: XML data binding

[edit] Command binding

Command bindings, commonly referred to as keyboard macros, or simply macros, are frequently built into professional quality computer applications. In many of these, bindings can be modified or added, but usually can not be removed (i.e., the keystroke combination cannot be unassociated from the function with which it is associated).

As an example of a command binding, most applications on Mac OS bind the "Save" menu item to the Command-S keyboard shortcut, so that Command-S can be used to save a document instead of having to navigate to that menu item each time. The Emacs text editor binds the "save-buffers-kill-emacs" command to the Control-X Control-C keystrokes in sequence, so that the user does not have to type "save-buffers-kill-emacs" whenever he/she wants to save and quit. Some computer applications, such as Microsoft Excel, allow the user to create a macro to do several common operations in sequence, and then bind a simple command to that macro to activate it.


Control bindings also exist in video games. A game might have a "shoot" control, which can be bound to any available key. A game like Tribes with complicated in-game menus can bind specific sequences of keys as shortcuts to menu items.

[edit] See also