usefor-article-08 August 2002
[< Prev]
[TOC] [ Next >]
2.4.3. Syntax copied from other standards
The following syntactic forms, taken from [RFC 2234] or from [RFC
2822], are repeated here for convenience only:
ALPHA = %x41-5A / ; A-Z
%x61-7A ; a-z
CR = %x0D ; carriage return
CRLF = CR LF
DIGIT = %x30-39 ; 0-9
HTAB = %x09 ; horizontal tab
LF = %x0A ; line feed
SP = %x20 ; space
NO-WS-CTL = %d1-8 / ; US-ASCII control characters
%d11 / ; which do not include the
%d12 / ; carriage return, line feed,
%d14-31 / ; and whitespace characters
%d127
specials = "(" / ")" / ; Special characters used in
"<" / ">" / ; other parts of the syntax
"[" / "]" /
":" / ";" /
"@" / "\" /
"," / "." /
DQUOTE
WSP = SP / HTAB ; whitespace characters
FWS = ([*WSP CRLF] 1*WSP); folding whitespace
ccontent = ctext / quoted-pair / comment
comment = "(" *([FWS] ccontent) [FWS] ")"
CFWS = *([FWS] comment) ( ([FWS] comment) / FWS )
DQUOTE = %d34 ; quote mark
quoted-pair = "\" text
atext = ALPHA / DIGIT /
"!" / "#" / ; Any US-ASCII character except
"$" / "%" / ; controls, SP, and specials.
"&" / "'" / ; Used for atoms
"*" / "+" /
"-" / "/" /
"=" / "?" /
"^" / "_" /
"`" / "{" /
"|" / "}" /
"~"
atom = [CFWS] 1*atext [CFWS]
dot-atom = [CFWS] dot-atom-text [CFWS]
dot-atom-text = 1*atext *( "." 1*atext )
qcontent = qtext / quoted-pair
quoted-string = [CFWS] DQUOTE
*( [FWS] qcontent ) [FWS]
DQUOTE [CFWS]
word = atom / quoted-string
phrase = 1*word
NOTE: Following [RFC 2234], literal text included in the syntax
is to be regarded as case-insensitive. However, in
contradistinction to [RFC 2822], the Netnews protocols are
sensitive to case in some instances (as in newsgroup-names, some
header parameters, etc.). Care has been taken to indicate this
explicitly where required.
As in [RFC 2822], where any quoted-pair appears it is to be
interpreted as its text character alone. That is to say, the "\"
character that appears as part of a quoted-pair is semantically
"invisible".
Again, as in [RFC 2822], strings of characters that include
characters not syntactically allowed in some particular context may
be incorporated into a quoted-string by "encapsulating" them between
quote (DQUOTE, US-ASCII 34) characters, prefixing every quote and
backslash character (and possibly other characters too) with a "\" so
as to form a quoted-pair, and possibly introducing folding by
prefixing some WSP with CRLF.
The semantic value of a quoted-string (i.e. the result of reversing
the encapsulation) is a string of characters which includes neither
the optional CFWS outside of the quote characters, nor the quote
characters themselves, nor any CRLF contained within any FWS between
the two quote characters, nor the "\" which introduces any quoted-
pair.
[< Prev]
[TOC] [ Next >]
#Diff to first older
--- ../usefor-article-07/Syntax_copied_from_other_standards.out May 2002
+++ ../usefor-article-08/Syntax_copied_from_other_standards.out August 2002
@@ -54,7 +54,7 @@
NOTE: Following [RFC 2234], literal text included in the syntax
is to be regarded as case-insensitive. However, in
contradistinction to [RFC 2822], the Netnews protocols are
- sensitive to case in some instances (as in newsgroup names, some
+ sensitive to case in some instances (as in newsgroup-names, some
header parameters, etc.). Care has been taken to indicate this
explicitly where required.