Source: Internet
Author: User


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



                                ; 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






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