From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailout.scc.kit.edu (mailout.scc.kit.edu [129.13.185.202]) by krisdoz.my.domain (8.14.5/8.14.5) with ESMTP id s7EG877X001127 for ; Thu, 14 Aug 2014 12:08:09 -0400 (EDT) Received: from hekate.usta.de (asta-nat.asta.uni-karlsruhe.de [172.22.63.82]) by scc-mailout-02.scc.kit.edu with esmtp (Exim 4.72 #1) id 1XHxZK-0006OB-2m; Thu, 14 Aug 2014 18:08:02 +0200 Received: from donnerwolke.usta.de ([172.24.96.3]) by hekate.usta.de with esmtp (Exim 4.77) (envelope-from ) id 1XHxZK-0003Yx-15; Thu, 14 Aug 2014 18:08:02 +0200 Received: from iris.usta.de ([172.24.96.5] helo=usta.de) by donnerwolke.usta.de with esmtp (Exim 4.72) (envelope-from ) id 1XHxZJ-0004QT-Ve; Thu, 14 Aug 2014 18:08:02 +0200 Received: from schwarze by usta.de with local (Exim 4.77) (envelope-from ) id 1XHxYZ-0002xf-6x; Thu, 14 Aug 2014 18:07:15 +0200 Date: Thu, 14 Aug 2014 18:07:14 +0200 From: Ingo Schwarze To: Guy Harris Cc: tech@mdocml.bsd.lv, jmc@openbsd.org Subject: Re: mdoc(7): improve description of .Em and .Sy Message-ID: <20140814160714.GE29858@iris.usta.de> References: <20140813212212.GG26534@iris.usta.de> <688F0B4B-25B9-4C50-8746-55AB04734189@alum.mit.edu> X-Mailinglist: mdocml-tech Reply-To: tech@mdocml.bsd.lv MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <688F0B4B-25B9-4C50-8746-55AB04734189@alum.mit.edu> User-Agent: Mutt/1.5.21 (2010-09-15) Hi Guy, Guy Harris wrote on Wed, Aug 13, 2014 at 03:54:55PM -0700: > On Aug 13, 2014, at 2:22 PM, Ingo Schwarze wrote: >> The central question is whether these macros should be considered >> as semantic or as physical markup. While the historic documents >> may slightly, if inconsistently, favour the semantic standpoint, >> in our MACRO OVERVIEW i called them "physical", and i'd like to >> stick with that, for the following reason: Even if we call them >> semantic, we have to define such a broad range of semantic >> meanings that translation into any other modern semantic markup >> language, in particular HTML, becomes impossible. In particular, >> sometimes .Em would have to become , sometimes , .Sy >> sometimes and sometimes , but there is no way to >> automatically decide which is the right one when finding one of >> these macros in a manual page, so we would have to fall back to >> physical markup anyway. Calling the physical also reflects actual >> usage better and isn't completely inconsistent with historical >> documentation. > Well, there's physical, as in "display this in italic characters", That's exactly what people usually mean when talking about physical (or presentational or visual) markup, see for example http://www.math.grin.edu/~rebelsky/Tutorials/Design/EdMedia97/logical-vs-physical.html http://www.augustana.ab.ca/~mohrj/courses/2000.fall/csc110/lecture_notes/html.html http://webtips.dan.info/logical.html http://www.cs.tut.fi/~jKorpela/HTML3.2/4.5.html ... > and there's physical, as in "present this in some form that > indicates emphasis"; the latter is "physical" in that it explicitly > affects presentation [...] "Affecting but not specifying presentation" is almost the definition of semantic (or logic or structural) markup, which is the opposite of physical markup. So i fear you are confusing the terms here. > Unfortunately, mdoc, unlike HTML, never had "display this in italic > characters", and somebody who had a reason to want the text displayed > in italic characters for reasons *other* than emphasis had to fall back > on .Em, Not quite. When the development of mdoc(7) started in about 1989, it predated HTML and the web, and people weren't aware at that time that the distinction of physical and semantic markup is all that important. For example Tim Barners-Lee's original WWW proposal does not mention "formatting" at all: http://www.w3.org/History/1989/proposal.html There is a document about future "HTML directions" as late as 1992 (!) talking about the possible introduction of and tags - that's what is called and now - mentioning the terms "physical" and "logical" markup, but not even mentioning that logical markup should usually be preferred: http://www.w3.org/History/19921103-hypertext/hypertext/WWW/MarkUp/Future.html People were blurry about it at the time, they didn't see that it matters, you can clearly see that here in the 4.3BSD-Reno text predating the HTML discussion by two years: Symbolic The symbolic request is really a boldface request. The need for this macro has not been established, it is included 'just in case'. Usage: .Sy symbol ... Example output: something bold Emphasis Request A portion of text may be stressed or emphasized with the .Em request. The font used is commonly italic. Usage: .Em argument ... One is described as physical ("boldface") with a fuzzy reference to semantics ("symbolic"), the other is described as semantic ("emphasized"). People just didn't care back then. That neglect persists in the groff documentation to this day. > so maybe retroactively redefining .Em to mean "display this in italic > characters" We are not retroactively redefining it. The code always did just that and the docs always hinted at both the formatting and the semantics. It's merely that at the time the documentation was written, people didn't care about the distinction ", usually used for " and ", usually formatted in ". So we are merely clarifying it. > is the least bad choice (adding .I to mdoc wouldn't help people who > want to write man pages that will work with older versions of mandoc > and with the mdoc macros). I don't see an urgent need to add any macros in this area either. Yours, Ingo -- To unsubscribe send an email to tech+unsubscribe@mdocml.bsd.lv