ISO/IEC 14977 : 1996(R2018)

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 of the notation and its graphical representation.