BS ISO/IEC 14977:1996

Foreword
Introduction
1 Scope
2 Normative references
3 Definitions
4 The form of each syntactic element of Extended BNF
    4.1 General
    4.2 Syntax
    4.3 Syntax-rule
    4.4 Definitions-list
    4.5 Single-definition
    4.6 Syntactic-term
    4.7 Syntactic exception
    4.8 Syntactic-factor
    4.9 Integer
    4.10 Syntactic-primary
    4.11 Optional-sequence
    4.12 Repeated-sequence
    4.13 Grouped sequence
    4.14 Meta-identifier
    4.15 Meta-identifier-character
    4.16 Terminal-string
    4.17 First-terminal-character
    4.18 Second-terminal-character
    4.19 Special-sequence
    4.20 Special-sequence-character
    4.21 Empty-sequence
    4.22 Further examples
5 The symbols represented by each syntactic element
    5.1 General
    5.2 Terminal-string
    5.3 Meta-identifier
    5.4 Grouped-sequence
    5.5 Optional-sequence
    5.6 Repeated-sequence
    5.7 Syntactic-factor
    5.8 Syntactic-term
    5.9 Single-definition
    5.10 Definitions-list
    5.11 Special-sequence
    5.12 Empty-sequence
6 Layout and Comments
    6.1 General
    6.2 Terminal-character
    6.3 Gap-free-symbol
    6.4 Gap-separator
    6.5 Commentless-symbol
    6.6 Comment-symbol
    6.7 Bracketed-textual-comment
7 The representation of each terminal-character in
    Extended BNF
    7.1 General
    7.2 Letters and digits
    7.3 Other terminal characters
    7.4 Alternative representations
    7.5 Other-character
    7.6 Gap-separator
    7.7 Terminal-characters represented by a pair of
          characters
    7.8 Invalid character sequences
8 Examples
    8.1 The syntax of Extended BNF
    8.2 Extended BNF used to define itself informally
    8.3 Extended BNF defined informally
Annexes
A Two-level grammars
B Bibliography

Specifies a notation, Extended BNF, for defining the syntax of a linear sequence of symbols. Specifies both the logical structure and its graphical representation.

This International Standard defines a notation, Extended BNF, for specifying the syntax of a linear sequence of symbols. It defines both the logical structure of the notation and its graphical representation.

Extended BNF has applications in the definition of programming and other languages, as well as in other formal definitions, for example the commands to an operating system, or the precise format of data and results.

Examples of Extended BNF are given in clause8.

NOTE— Like many other notations, Extended BNF can still be misused; thus it does not prevent someone from trying to define an unparsable or ambiguous language.