Predeclared

In computer languages, the built-in information, encodings or tools that are available to a programmer are pre-declared, often in the form of entities, variables, objects, functions or instructions. It is mostly not possible to overwrite or otherwise manipulate them.

In computer languages, the built-in information, encodings or tools that are available to a programmer are pre-declared, often in the form of entities, variables, objects, functions or instructions. It is mostly not possible to overwrite or otherwise manipulate them. == Pre-declared object== Pre-declared objects have the same goal as pre-declared variables. For example, in the JavaScript language, the navigator-object is available to get all kinds of information about the browser that is running the script in question. A = 1; By declaring the name A, the program creates a namespace for the variable called A. In most modern languages, the variable does not need to be pre-declared on a separate line, as the following instruction achieves exactly the same: var A = 1; In early computer languages, the variable always needed to be pre-declared as a separate instruction, because the operating system had to reserve a series of bytes in the available RAM, before the actual value of the variable could be stored in it. Declaration and assignment are still two fundamental different things, though they nowadays mostly appear in a same instruction line. ==References==

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