Editing Backus–Naur form (section)

=== ABNF ===
{{Main|ABNF}}
[[Augmented Backus–Naur form]] (ABNF) and Routing Backus–Naur form (RBNF)<ref>[http://tools.ietf.org/html/rfc5511 RBNF].</ref> are extensions commonly used to describe [[Internet Engineering Task Force]] (IETF) [[protocol (computing)|protocol]]s.

[[Parsing expression grammar]]s build on the BNF and [[regular expression]] notations to form an alternative class of [[formal grammar]], which is essentially [[analytic grammar|analytic]] rather than [[generative grammar|generative]] in character.