Reserved Word
Reserved words (occasionally called keywords) are one type of grammatical construct in programming languages. These words have special meaning within the language and are predefined in the language’s formal specifications. Typically, reserved words include labels for primitive data types in languages that support a type system, and identify programming constructs such as loops, blocks, conditionals, and branches.
The list of reserved words in a language are defined when a language is developed. Occasionally, depending on the flexibility of the language specification, vendors implementing a compiler may extend the specification by including non-standard features. Also, as a language matures, standards bodies governing a language may choose to extend the language to include additional features such as object-oriented capabilities in a traditionally procedural language. Sometimes the specification for a programming language will have reserved words that are intended for possible use in future versions. In Java, const
and goto
are reserved words — they have no meaning in Java but they also cannot be used as identifiers. By "reserving" the terms, they can be implemented in future versions of Java, if desired, without "breaking" older Java source code. Reserved words may not be redefined by the programmer, unlike predefined functions, methods, or subroutines, which can often be overridden in some capacity. The name of a predefined function, method, or subroutine is typically categorized as an identifier instead of a reserved word.
Read more about Reserved Word: Reserved Word Vs. Keyword, Comparison By Language, Reserved Words and Language Independence
Famous quotes containing the words reserved and/or word:
“The men the American people admire most extravagantly are the most daring liars; the men they detest most violently are those who try to tell them the truth. A Galileo could no more be elected President of the United States than he could be elected Pope of Rome. Both posts are reserved for men favored by God with an extraordinary genius for swathing the bitter facts of life in bandages of soft illusion.”
—H.L. (Henry Lewis)
“You have no word for soldiers to enjoy
The feel of, as an apple, and to chew
With masculine satisfaction. Not good-by!
Come back!or careful! Look, and let him go.”
—Gwendolyn Brooks (b. 1917)