Backus-Naur Form

The Backus-Naur Form, which is as well called the BNF, the Backus Normal Form and or the Backus-Naur formalism, is a notation used in the description of a part of syntax of sentences of a language. In about 1959, the Backus-Naur Form was suggested by stern Backus, a constituent or part of the thirteen members which comprise the Algol 60 committee. Moreover, John Backus, besides from being a constituent of IBM, is also a major(ip) figure responsible for FORTRAN.The Backus-Naur Form, has been used since then to describe the syntax of Algol 60. The BNF along wit its extensions have become standard tools for describing the syntax of programming notations, and in many cases, parts of compliers argon generated automatically from a BNF description (Gries, 1981). The precondition of the Backus-Naur Form includes a set of derivation rules. This set of deviation rules be written as = . The in this formula is considered to be nonterminal.The sequences of symbols create the replete(p) ex pression. Furthermore, sequences separated by a vertical bar , may also consist the expression. The sign is made use of in order to invest out a definite choice. Expression which are not strand on the left side, are considered to be terminals. In the present, Backus-Naur Form specifications are created in a form which it is easily read by humanness and oftentimes, they are informal, including certain syntax rules and extensions (Bergin, 1996).Syntax rules and extensions state that optional items should be enfold in square brackets, like in and that items which repeat or legislate 0 or more times should be enclosed in curly brackets, such as in = . While, items which repeat or make it 1 or more times should be followed using a +. Syntax rules and extension also state that the non-terminals should be written or typed using plain text, instead of using italics and angle brackets. While the terminals come in in bold.Optional choices in a production should be separated wi th the use of the vertical bar symbol, like in . If an item in the Backus-Naur Form is repeated, an asterisk * should be placed after the item and that guileless parenthesis are used, by enclosing the item, to group the items (Chomsky, 1957). References Bergin, T. J. , & Gibson, R. G. (1996). History of scheduling Languages. New York Academic Press. Chomsky, N. (1957). Syntactic Structures. Mouton The Hague. Gries, D. (1981). The Science of Programming Springer-Verlag.