Re: Offtopic: Web Standards Project

John Cowan (cowan@locke.ccil.org)
Tue, 11 Aug 1998 12:09:09 -0400


Toby Speight wrote:

> Well, I'm sure there would be plenty here who'd like to know. ASCII
> is a 7-bit character coding scheme - nothing more, nothing less. The
> term "8-bit ASCII" could be used to refer to any of a number of 8-bit
> codes which coincide with ASCII for values under 128: ISO-8859-1,
> ISO-8859-2, ..., ISO-8859-9, ISO-2022-JP (I think), the Windows and
> Macintosh character sets, and others.

ISO/IEC 8859-1 is, or was, reimplemented as an American National
Standard under the title "8-bit American Standard Code for Information
Interchange", i.e. "8-bit ASCII". (I can't find this in the current
ANSI catalog, so it may have been revoked in favor of 8859-1.)

However, this has nothing to do with the charset name "US-ASCII",
which refers only to 7-bit ISO/IEC 646:1991, which is the same as
7-bit ASCII, ANSI X3.4.

> [BTW, when using US-ASCII as an entity character encoding, must one
> declare it as UTF-8, and use other means to ensure that multi-byte
> characters don't occur?]

No, you can declare it as "US-ASCII". In theory, parsers may throw
a fatal error because they don't support that encoding. In practice,
no parser is at all likely to do so.

-- 
John Cowan	http://www.ccil.org/~cowan		cowan@ccil.org
	You tollerday donsk?  N.  You tolkatiff scowegian?  Nn.
	You spigotty anglease?  Nnn.  You phonio saxo?  Nnnn.
		Clear all so!  'Tis a Jute.... (Finnegans Wake 16.5)