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Extended Backus–Naur form

In computer science, extended Backus–Naur form (EBNF) is a family of metasyntax notations, any of which can be used to express a context-free grammar. EBNF is used to make a formal description of a formal language such as a computer programming language. They are extensions of the basic Backus–Naur form (BNF) metasyntax notation. The earliest EBNF was…

Standards & Science

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Research this topic

Explore the main themes, entities and connections around Extended Backus–Naur form. Start with the topic map, then use the sections below for research and deeper semantic analysis.

Explore this topic

Start with a few of the strongest sections from the source topic. These are research directions, not a list of keywords you must use.

Basics

CodeSyntaxNonterminalAlphanumeric charactersPunctuation marks
10 related topics

Examples

Syntax diagramPascalControl flows
3 related topics

Advantages over BNF

GrammarTerminals
2 related topics

Conventions

HyphensApostrophe
2 related topics

Topics to explore

Browse the full topic structure. Each item opens a new analysis centered on that subject.

Overview

Basics

Examples

Advantages over BNF

Conventions

Extensibility

  • Lisp Lisp (programming language)

Advanced semantic analysis

Deeper signals for content research, entity SEO and topical coverage. The plain-language headings explain what each technical view is useful for.

Map overview Semantic statistics

Extended Backus–Naur form

Nodes35
Edges34
Triples1
Avg. degree1.94
Density0.057143
Components1

How this topic connects Entity context

See the strongest relationship patterns around the current topic before diving into the raw triples.

Important terminology Word statistics

Use these terms to understand the vocabulary surrounding the topic, not as a checklist for keyword stuffing.

Important terminology

ebnf bnf iso standard used syntax extended grammar examples terminal following defined iec 14977 symbols also rule notation use conventions

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
a computer programming languageinstance ofEBNF is used to make a formal description of a formal language0.80text

Related concept clusters Concept neighborhoods

These clusters group vocabulary that occurs around closely connected concepts in the source material.

    Connections between topic areas Semantic bridges

    Bridges can reveal useful research angles that are easy to miss in a flat list of related terms.

    Min side: 3
    For writers, content strategists, SEOs, marketers and creators — from quick topic research to advanced semantic analysis.