Re: Processing instructions for style tweaks?

Daniel W. Connolly (
Wed, 30 Nov 1994 11:54:51 -0600

In message <>, Paul Grosso writes:
>> Subject: Re: Processing instructions for style tweaks?
>> Date: Wed, 30 Nov 1994 10:39:36 -0500 (EST)
>> From: Murray Maloney <>
>> I am dead set against PIs. Sure we could develop conventions,
>> but they could never be verified as conforming by an SGML parser.
>> No, PIs are bad! PIs are worse even than format-specific
>> SGML elements like <I> and <B> which can readily be mapped
>> to any formatting desired at the reader's end.
>> . . .
>I don't want to come out as if I'm championing PIs. I believe in
>"clean SGML" [Sharon Adler used to talk of "polluting" the SGML
>with format information] as much as anyone.
>But, as Murray elegantly pointed out in the rest of his post (that
>I elided), we must allow for other people with other viewpoints.
>In particular, there are (at least sometimes for some people) good
>reasons for wanting more control over style that can be achieved
>via, say, DSSSL Lite location/query mechanisms.
>However, I do disagree with "PIs are worse even than format-specific
>SGML elements." I think you're wrong, here, Murray. Having formatting
>markup *indistinguishable* from structural markup (i.e., having it all
>be DTD elements--some with "good semantics" and some with "bad semantics")
>is the worst way to go.
>The advantage of using PIs for formatting-specific markup is that it's
>easy to strip/ignore them when one wants to slough off the "pollution"
>of embedded format-specific information.


>Finally, using formatting elements doesn't solve many of the problems
>because they either can't be used everywhere one might want, or their
>content models have to be so lax as to destroy the structure of the
>original DTD. PIs don't have to drastically change the ESIS tree of
>the document.

Yeah... what he said.