- From: Harold A. Driscoll <harold@driscoll.chi.il.us>
- Date: Fri, 15 Nov 1996 20:46:25 -0600
- To: "Carl Morris" <msftrncs@htcnet.com>
- Cc: <marc@ckm.ucsf.edu>, "WWW HTML List" <www-html@w3.org>
At 19:01 15/11/96 -0600, Carl Morris wrote: >I am going to pick on people with this: > ><! is a comment in HTML > While you'd apparently like to consider anything beginning with a <! a comment, the HTML specification [1] takes a very different view of the matter. [quoted below] ><! -- this is a comment in SGML -- > > >Why? An HTML parser has no business trying to figure out SGML, an SGML >parser being used on an HTML document on the other hand may have use >for the declaration. It needs to be described this way. Quite to the contrary. Since HTML is (by definition, see RFC 1866 in the Abstract) an application of SGML, SGML parsers are quite appropriate HTML parsers. >Calling <! > not an HTML comment is misleading to those people who have >no use for SGML. Actually, calling <! a comment open symbol is what is misleading, since it is incorrect. Please, to keep this discussion on track, it would be very helpful to cite references for facts, and to clearly identify opinions which differ from the facts as such. The notation used for SGML comments, and that used for SGML DOCTYPEs, might certainly seem "weird" to some folks unfamiliar with them. But, like many conventions (both social and technical) in life, a degree of consistency and predictability is more important (more valuable) than occasional shortening of notation. In both the cases (comments and DOCTYPE) there are strong benefits from following established conventions [2] which far outweigh the casual disadvantages. /Harold [1] RFC 1866 PS T. Berners-Lee, D. Connolly, "Hypertext Markup Language - 2.0", 11/03/1995. (Pages=77) (Format=.txt) http://ds.internic.net/rfc/rfc1866.txt 3.2.5. Comments To include comments in an HTML document, use a comment declaration. A comment declaration consists of `<!' followed by zero or more comments followed by `>'. Each comment starts with `--' and includes all text up to and including the next occurrence of `--'. In a comment declaration, white space is allowed after each comment, but not before the first comment. The entire comment declaration is ignored. NOTE - Some historical HTML implementations incorrectly consider any `>' character to be the termination of a comment. For example: <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN"> <HEAD> <TITLE>HTML Comment Example</TITLE> <!-- Id: html-sgml.sgm,v 1.5 1995/05/26 21:29:50 connolly Exp --> <!-- another -- -- comment --> <!> </HEAD> <BODY> <p> <!- not a comment, just regular old data characters -> [2] Consider the historical case of distinguishing between the number zero and the letter O. For many years, engineers have used a slash through the number 0. This convention was implemented in a number of hardware devices, including various IBM printers during the mainframe era. Apparently ignorant of this convention, an minister turned computer programming book author noted the confusion and introduced the convention of using a slash through the letter O. As you can imagine, while each usage was rather arbitrary, things got very confusing when programmers (using slash with letter O) got their printouts (using slash with number 0). -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Harold A. Driscoll mailto:harold@driscoll.chi.il.us #include <std/disclaimer> http://homepage.interaccess.com/~driscoll/
Received on Friday, 15 November 1996 21:46:55 UTC