Augmented BNF for Syntax Specifications: ABNF

The Internet Engineering Steering Group (IESG) announced the approval
of the "Augmented BNF for Syntax Specifications: ABNF" specification as
a Full IETF Standard. ABNF is used for formal language description in
IETF RFCs, W3C specifications, and elsewhere. The document was reviewed
by Bill Fenner, Frank Ellerman, Julian Reschke, Steven Legg, Alexey
Melnikov. An implementation report is available. Abstract: "Internet
technical specifications often need to define a formal syntax. Over
the years, a modified version of Backus-Naur Form (BNF), called Augmented
BNF (ABNF), has been popular among many Internet specifications. The
current specification documents ABNF. It balances compactness and
simplicity, with reasonable representational power. The differences
between standard BNF and ABNF involve naming rules, repetition,
alternatives, order-independence, and value ranges. This specification
also supplies additional rule definitions and encoding for a core
lexical analyzer of the type common to several Internet specifications. More Information
See also the implementation report: Click Here