I think esr is emphasizing (!) that in a structural-markup language the tags can have no typographic meaning whatsoever. While it may be possible to mimic the tags of structural markup in a presentation-markup language, there is power in completely and firmly separating the two aspects: you can then independently develop the two aspects; indeed the typographic aspect can come to embrace completely new and even unexpected media whereas the structural aspect remains the same. If you tie yourself to a presentation-markup language, there is no guarantee that a user has not made use of the presentation-markup language in such a way that it is impossible to migrate cleanly to a different structural markup or presentation. Indeed, it has been the norm for users to reach for low-level commands while using high-level packages in groff or (La)TeX. Neither system prevents the user in any way from being "non-structural". --d
>________________________________ >From: Anton Shepelev <anton....@gmail.com> >To: groff@gnu.org >Sent: Thursday, May 3, 2012 11:21 AM >Subject: [Groff] Eric Raymond on groff and TeX > >I accidently came upon what seems to me an unfair >judgement about groff and TeX: > > As an example: In a presentation-markup lan- > guage, if you want to emphasize a word, you > might instruct the formatter to set it in > boldface. In troff(1) this would look like > so: > > All your base > .B are > belong to us! > > In a structural-markup language, you would > tell the formatter to emphasize the word: > > All your base <emphasis>are</emphasis> belong to us! > > The "<emphasis>" and </emphasis>in the line > above are called markup tags, or just tags > for short. They are the instructions to your > formatter. > > In a structural-markup language, the physi- > cal appearance of the final document would > be controlled by a stylesheet . It is the > stylesheet that would tell the formatter > "render emphasis as a font change to bold- > face". One advantage of structural-markup > languages is that by changing a stylesheet > you can globally change the presentation of > the document (to use different fonts, for > example) without having to hack all the the > individual instances of (say) .B in the doc- > ument itself. > >Source: > > http://tldp.org/HOWTO/DocBook-Demystification-HOWTO/x69.html > >Should we, maybe, ask the author to correct it, for >I think, groff and TeX macro packages do provide a >means for structural mark-up, and, considering the >example above, it is of course possible to redefine >the macro .B to achieve the desired result? For >clarity, it could also be renamed as "EMPH". > >In my understanding, a package provides both con- >structs for structural mark-up and means to modify >their underlying "presentation", and the one is very >loosely coupled with the other, allowing to change >"presentation" without affecting the "structure" and >vice versa... > >Anton > > > >
