Augmented BNF for Syntax SPECIFICATIONS:ABNF

Original: http://tools.ietf.org/html/rfc5234

Core Rules

Certain Basic rules are in uppercase, such as Sp,htab, CRLF, DIGIT,

ALPHA, etc.

 

ALPHA =%x41-5a/%x61-7a; A-Z/ A-Z

 

BIT = "0"/"1"

 

CHAR =%x01-7f

; any 7-bitus-ascii character,

                                ; Excluding NUL

 

 

 

CR =%x0d

; Carriagereturn

 

CRLF = CR LF

                                ; Internet Standardnewline

 

CTL =%x00-1f/%x7f

; Controls

 

DIGIT =%x30-39

; 0-9

 

dquote =%x22

                                ; "(Double Quote)

 

Hexdig = DIGIT/"A"/"B"/"C"/"D"/"E"/"F"

 

Htab =%x09

; Horizontaltab

 

LF =%x0a

; linefeed

 

lwsp = * (Wsp/crlf WSP)

                                ; Use of Thislinear-white-space rule

                                ; Permits lines containing

                                ; Space this are no longer legal in

                                ; Mail headers and have caused

                                ; Interoperability problems in the other

                                ; Contexts.

                                ; Do not usewhen defining mail

                                ; Headers with the caution in

                                ; Other contexts.

 

octet =%x00-ff

; 8 bits Ofdata

 

SP =%x20

 

Vchar =%x21-7e

; visible (printing) characters

 

WSP = Sp/htab

;