Backus Naur Form Beispiel
In computer science backus naur form pronunciation or backus normal form bnf is a metasyntax notation for context free grammars often used to describe the syntax of languages used in computing such as computer programming languages document formats instruction sets and communication protocols they are applied wherever exact descriptions of languages are needed.
Backus naur form beispiel. Backus naur notation shortly bnf is a formal mathematical way to describe a language to the backus naur form is a way of defining syntax. For instance in. Bnf backus naur form is a syntactic metalanguage i e a language about a language. B backus naur form syntax.
Find out more about how this works in today s random wedne. Backus naur form bnf is a notation for expressing the grammar of a language in the form of production rules. The standard technique for defining the syntax of a computer language is to use backus naur form bnf. Braces enclose a choice of items only one of which is required.
Like the bnf is given for a postal address can see below. The metalanguage is a formal notation for specifying the grammar that describes the syntax of a programming language. The syntax in this reference is presented in a simple variation of backus naur form bnf that uses the following symbols and conventions. This is a short introduction to the backus naur form of describing a context free grammar with some simple examples.
Postal address name part street address zip part name part persona1 part last name opt suffix part eol. Bnf or backus naur form is an elegant and succinct way of expressing a grammar in very few lines. Each graphic syntax diagram in this book is followed by a link to a text description of the graphic. The text descriptions are a simple variant of backus naur form bnf syntax that includes the symbols and conventions explained in table b 1.
Symbol or convention description brackets enclose optional items. Qlikview backus naur form examples. And non terminals which can be expanded into one or more terminals and non terminals. Bnf was originally developed by john backus and subsequent contribution from peter naur to describe the syntax of algol 60 programming.