difference between TeX behavior and ConTeXt

difference between TeX behavior and ConTeXt

[Lars Huttar]

Hello,

I've been reading through the TeXbook to solidify the foundations for
TeX programming. In an exercise on roman and italic text, ConTeXt seems
to behave differently from what the book specifies (Plain TEX) at a
fairly fundamental level.

Exercise 4.1 says, "Explain how to typeset a roman word in the midst of
an italicized sentence."
I wrote, and the solution in the appendix says,
	{\it Explain how to typeset a\/ {\rm roman} word
	 in the midst of an italicized sentence.}

But when I typeset this using texexec, the word "roman" appears in
italic, just like the rest of the sentence.

I tried this on both Windows XP and Ubuntu Linux, with both PDFTex and
Xetex engines. On Windows I'm using ConTeXt minimal, and on Linux I'm
using ConTeXt from the TeXLive 2008 CD. The result is the same in all
cases: all the text is italicized.

Does this difference in behavior represent a known "feature" of ConTeXt?
If so, is it a difference in the defined behavior of \rm?

When I put \show\rm in the .tex file to display the definition of the
\rm macro, and run texexec, I get:
	> \rm=\protected macro:
	->\setcurrentfontstyle {rm}.
	l.7 \show\rm
By contrast, according to
http://webpages.charter.net/davidlha/.trm/trmi.html, "Plain TeX defines
\rm to be `\fam=0 \tenrm'."
So clearly the definition of the \rm macro is different in ConTeXt than
it is in Plain TeX.

I could understand ConTeXt possibly changing the details of \rm's
definition, e.g. a change in default font family; but it would really be
surprising to find that the logic of \rm's behavior has been changed.

Please help me understand if this is a bug or if there is a design
principle of ConTeXt that I should be aware of...

Thanks,
Lars
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Re: difference between TeX behavior and ConTeXt

[Aditya Mahajan]

On Tue, 25 Nov 2008, Lars Huttar wrote:

> Hello,
>
> I've been reading through the TeXbook to solidify the foundations for
> TeX programming. In an exercise on roman and italic text, ConTeXt seems
> to behave differently from what the book specifies (Plain TEX) at a
> fairly fundamental level.
>
> I could understand ConTeXt possibly changing the details of \rm's
> definition, e.g. a change in default font family; but it would really be
> surprising to find that the logic of \rm's behavior has been changed.
>
> Please help me understand if this is a bug or if there is a design
> principle of ConTeXt that I should be aware of...

It is a design decision. See the chapter of typography 
(http://context.aanhet.net/svn/contextman/context-reference/en/co-typography.pdf) 
in the new manual (under preparation).

Aditya
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Re: difference between TeX behavior and ConTeXt

[Lars Huttar]

On 11/25/2008 3:21 PM, Lars Huttar wrote:
....
> When I put \show\rm in the .tex file to display the definition of the
> \rm macro, and run texexec, I get:
> 	> \rm=\protected macro:
> 	->\setcurrentfontstyle {rm}.
> 	l.7 \show\rm
> By contrast, according to
> http://webpages.charter.net/davidlha/.trm/trmi.html, "Plain TeX defines
> \rm to be `\fam=0 \tenrm'."
> So clearly the definition of the \rm macro is different in ConTeXt than
> it is in Plain TeX.
> 

P.S. The same TeX reference reports,

"This switch plus the assignments made by Plain TeX are what makes
`${\rm text }$' typeset `text' in roman instead of in italics [154]."
where [154] refers to the page number in the TeXbook.

The latter says "The control sequence \rm is an abbreviation for '\fam=0
\tenrm'; thus, \rm causes \fam to become zero, and it makes \tenrm the
"current font." In horizontal mode, the \fam value is irrelevant and the
current font governs the typesetting of letters; ... [stuff about math
mode, which doesn't seem to apply to this situation]."

FWIW.
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Re: difference between TeX behavior and ConTeXt

[Lars Huttar]

On 11/25/2008 3:27 PM, Aditya Mahajan wrote:
> On Tue, 25 Nov 2008, Lars Huttar wrote:
> 
>> Hello,
>>
>> I've been reading through the TeXbook to solidify the foundations for
>> TeX programming. In an exercise on roman and italic text, ConTeXt seems
>> to behave differently from what the book specifies (Plain TEX) at a
>> fairly fundamental level.
>>
>> I could understand ConTeXt possibly changing the details of \rm's
>> definition, e.g. a change in default font family; but it would really be
>> surprising to find that the logic of \rm's behavior has been changed.
>>
>> Please help me understand if this is a bug or if there is a design
>> principle of ConTeXt that I should be aware of...
> 
> It is a design decision. See the chapter of typography 
> (http://context.aanhet.net/svn/contextman/context-reference/en/co-typography.pdf) 
> in the new manual (under preparation).
> 
> Aditya

Thanks for the explanation.
I hope that when the manual is finished it will make this clearer.
Currently, the draft chapter says
"As will be explained later, the command \rm is used to switch to a
roman/serif/regular style"
which does not seem to be happening.

The explanation of \em shows that ConTeXt's \em has different behavior
from Plain TeX's \it (especially when nesting styles), but doesn't say
that \it or \rm have changed behavior.

Lars
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Re: difference between TeX behavior and ConTeXt

[Rory Molinari]

Lars Huttar wrote:

> 
> Thanks for the explanation.
> I hope that when the manual is finished it will make this clearer.
> Currently, the draft chapter says
> "As will be explained later, the command \rm is used to switch to a
> roman/serif/regular style"
> which does not seem to be happening.

I think it is due to a difference in terminology between (plain) TeX and 
ConTeXt.

Knuth uses "roman" to mean "with serifs and not slanted" while ConTeXt 
uses it to mean just "not sans serif".  So something like

aardvark {\it aardvark {\rm aardvark}}

is really doing something like:

- Set "aardvark" in the default face (which is probably an unslanted serif)
- Switch to the italic "flavor" of the default face, which here means a 
traditional italic
- While in the italic flavor, switch to a roman "base".  But we already 
had a roman "base" so this doesn't change anything: we are still slanted 
because of the enclosing \it.

"Roman" and "italic" are on different axes and can be changed independently.


However, things are different if we start off in a sans serif face, like

\ss aardvark {\it aardvark {\rm aardvark}}

Now the \it still gives slanted text, but since the "base" is sans serif 
we don't get the traditional "italic" appearance that corresponds to a 
roman "base".  The nested \rm now does that.

(Note: my terminology is all wrong.  "Base" and "flavor" aren't the 
right terms at all, but I cannot remember the correct terms right now. 
I would be grateful is someone could correct me.)

Cheers,
Rory



> 
> The explanation of \em shows that ConTeXt's \em has different behavior
> from Plain TeX's \it (especially when nesting styles), but doesn't say
> that \it or \rm have changed behavior.
> 
> Lars
> ___________________________________________________________________________________
> If your question is of interest to others as well, please add an entry to the Wiki!
> 
> maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
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> ___________________________________________________________________________________

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Re: difference between TeX behavior and ConTeXt

[Idris Samawi Hamid ادريس سماوي حامد]

Hi,

On Tue, 25 Nov 2008 14:29:09 -0700, Lars Huttar <lars_huttar@sil.org>  
wrote:

> P.S. The same TeX reference reports,

Be careful, PlainTeX is a macropaackage, just as ConTeXt is. One must  
distinguish PlainTeX commands from the TeX (and pdftex/luaTeX) primitives.  
Although some PlainTeX commands work similarly to the ConTeXt  
counterparts, you can rarely assume this. There are lots and lots more  
examples. Better to just treat them as very distinct macropackages, with a  
few commonly USED command names in common, but used to MENTION different  
things.

Best wishes
Idris

-- 
Professor Idris Samawi Hamid, Editor-in-Chief
International Journal of Shi`i Studies
Department of Philosophy
Colorado State University
Fort Collins, CO 80523
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Re: difference between TeX behavior and ConTeXt

[Lars Huttar]

On 11/25/2008 5:37 PM, Rory Molinari wrote:
> Lars Huttar wrote:
> 
>> Thanks for the explanation.
>> I hope that when the manual is finished it will make this clearer.
>> Currently, the draft chapter says
>> "As will be explained later, the command \rm is used to switch to a
>> roman/serif/regular style"
>> which does not seem to be happening.
> 
> I think it is due to a difference in terminology between (plain) TeX and 
> ConTeXt.
> Knuth uses "roman" to mean "with serifs and not slanted"

Interesting.
As a newbie to typesetting, reading the TeXbook, I certainly wondered
which "axes" Knuth meant 'roman' to refer to... he simply describes it
as 'normal "roman"' and gives a visual example. So far, all I'd gathered
was that it meant "not italic."

Now that you brought up serifs, I read further in the chapter where
Knuth introduces \rm (ch. 4). He eventually makes clear that he does not
contrast roman with sans-serif (nor with slanted!), because he mentions
both slanted roman (p. 13) and the approved use of \rm to be temporarily
defined to mean a sans-serif type (p. 15). Apparently the only thing
roman is contrasted with in Knuth's book is "italic" (i.e. the modified
glyph style of an italic font, regardless of the slant).

Out of curiosity, I looked up 'roman' with regard to typography on
wikipedia. On the disambiguation page for Roman it says "Roman type, an
upright typeface style, contrasted to italic". But on the Roman_type
page it lists both "not-italic" and "with-serif" as (separate) senses of
"roman". Thanks for the tip.


Regardless of the terminology used, though, what is objectively clear is
that \rm has different effects on font settings in ConTeXt than in Plain
TeX. The TeXbook makes clear by example, if not by statement, that one
of the effects of '\rm' must be to make text non-italicized (also
non-slanted).

If it's designed not to do that in ConTeXt -- i.e. the ConTeXt designers
decided to change the semantics of one of the basic control sequences in
TeX, rather than merely providing a different one with new semantics --
you would think one would want that to be prominently documented. (Maybe
some flashing orange lights? :-)

Whereas \rm is not found at all in the command reference at
http://texshow.contextgarden.net/


> while ConTeXt
> uses it to mean just "not sans serif".

I wonder if the command sequence \serif was already taken?
That would certainly be less ambiguous and confusing...


> So something like
> 
> aardvark {\it aardvark {\rm aardvark}}
> 
> is really doing something like:
> 
> - Set "aardvark" in the default face (which is probably an unslanted serif)
> - Switch to the italic "flavor" of the default face, which here means a 
> traditional italic
> - While in the italic flavor, switch to a roman "base".  But we already 
> had a roman "base" so this doesn't change anything: we are still slanted 
> because of the enclosing \it.
> 
> "Roman" and "italic" are on different axes and can be changed independently.

It makes sense for "italicness" and "serifity" to be independently
changeable.
What's discouraging to me as a entrant to the whole TeX world (but an
experienced programmer) is the (apparently undocumented) redefinition of
a well-established control sequence that used to mean "non-italic" to
mean something different (maybe "serif" -- I still don't know for sure).

If I were choosing a TeX macro package at this point, I would definitely
 look for one that kept semantics of basic TeX command sequences
consistent with the intent expressed in the TeXbook... to avoid package
lock-in, as well as to make the learning curve easier and to be able to
use the resources of the whole TeX community.

That being said, I appreciate the design goals of ConTeXt, including the
desire to have independent controls for +/- italic, +/- serif, etc. I'm
also amazed at the energy that Hans still devotes to answering questions
on this mailing list, 18 years after ConTeXt was written! That's dedication.

Sorry if the above sounds too negative. After all, the TeXbook itself
does not make the semantics of \rm obvious.
However, once you dig deep enough it becomes clear that \rm does mean
"switch to a non-italic typeface" in Plain TeX.


> 
> However, things are different if we start off in a sans serif face, like
> 
> \ss aardvark {\it aardvark {\rm aardvark}}
> 
> Now the \it still gives slanted text, but since the "base" is sans serif 
> we don't get the traditional "italic" appearance that corresponds to a 
> roman "base".  The nested \rm now does that.
> 
> (Note: my terminology is all wrong.  "Base" and "flavor" aren't the 
> right terms at all, but I cannot remember the correct terms right now. 
> I would be grateful is someone could correct me.)
> 
> Cheers,
> Rory
> 

Lars

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Re: difference between TeX behavior and ConTeXt

[Lars Huttar]

On 11/25/2008 10:15 PM, Idris Samawi Hamid ادريس سماوي حامد wrote:
> Hi,
> 
> On Tue, 25 Nov 2008 14:29:09 -0700, Lars Huttar <lars_huttar@sil.org>  
> wrote:
> 
>> P.S. The same TeX reference reports,
> 
> Be careful, PlainTeX is a macropaackage, just as ConTeXt is. One must  
> distinguish PlainTeX commands from the TeX (and pdftex/luaTeX) primitives.  
> Although some PlainTeX commands work similarly to the ConTeXt  
> counterparts, you can rarely assume this. There are lots and lots more  
> examples. Better to just treat them as very distinct macropackages, with a  
> few commonly USED command names in common, but used to MENTION different  
> things.

Ah...
thanks...

Lars

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Re: difference between TeX behavior and ConTeXt

[Peter Münster]

On Tue, Nov 25 2008, Lars Huttar wrote:

> If it's designed not to do that in ConTeXt -- i.e. the ConTeXt designers
> decided to change the semantics of one of the basic control sequences in
> TeX, rather than merely providing a different one with new semantics --
> you would think one would want that to be prominently documented. (Maybe
> some flashing orange lights? :-)

Hello Lars,

It's in chapter 5 of the user manual (without flashing orange lights):
http://www.pragma-ade.com/general/manuals/cont-eni.pdf or
http://www.pragma-ade.com/general/manuals/cont-enp.pdf

Cheers, Peter

-- 
http://pmrb.free.fr/contact/

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Re: difference between TeX behavior and ConTeXt

[Marcin Borkowski]

Dnia Tue, Nov 25, 2008 at 10:30:51PM -0600, Lars Huttar napisał(a):
> It makes sense for "italicness" and "serifity" to be independently
> changeable.
> What's discouraging to me as a entrant to the whole TeX world (but an
> experienced programmer) is the (apparently undocumented) redefinition of
> a well-established control sequence that used to mean "non-italic" to
> mean something different (maybe "serif" -- I still don't know for sure).

Hi,

and welcome to the TeX world;).

Me not being an experienced programmer, but (some kind) of more or less
experienced TeX user, I'd add the following.

In general, there are three 'mainstream' TeX macropackages: plain TeX
(say, plus AMSTeX), LaTeX and ConTeXt.

It seems that the majority of the TeX world uses LaTeX; most people,
when they say "TeX", mean essentially "LaTeX".  LaTeX is a a big beast,
and if you are new to TeX _and_ don't want to submit papers to math/cs
journals (which are seldom aware of ConTeXt, I'm afraid), learning LaTeX
may not be exactly what you want.

There is also a very small minority using plain TeX (including Knuth,
who doesn't use LaTeX; he was once asked why, and said: "I'm afraid of
large systems";)).  The TeXbook is about two things: plain TeX and using
the TeX engine itself.

Then there is another minority (but growing, I believe) of ConTeXt
users.  For example, I am a plain-to-LaTeX and then (after 5 years or
so) LaTeX-to-ConTeXt convert (still using LaTeX when writing papers
which I want to submit somewhere, though, and plain TeX when doing
something really atypical).

It is probably true that plain TeX is weird and "incomplete" in a sense.
What \rm means in plain TeX is: "switch to upright, serif font in 10pt
size".  It _might_ be modified (in the TeXbook spirit) to, e.g., "switch
to upright, serif font in _current_ size" - but please note that plain
TeX itself has _no_ notion of "current size" (or, in other words,
"current size" in plain TeX is fixed at 10pt).  What Knuth mentions in
the TeXbook is that you might want to write some macros to introduce
something like a flexible "current size" - he even shows how to do it in
Appendix E - but it is no longer plain vanilla TeX then!  So what you
did was to extrapolate plain TeX's meaning of \rm to a situation outside
plain TeX itself (although in Knuthian spirit).

So, everything I said above is trivial when applied just to \rm, but I
wanted to try to explain the differences between plain TeX, LaTeX and
ConTeXt.  So to finish this explanation, I would say the following:

* Plain TeX is a DIY thing.  Cross-references, automatic numbering of
chapters etc., bibliographies, including graphics, etc., etc. -
forget it, it just isn't there.  This is very fine if you're doing
something really unusual (and this happens from time to time) and don't
need such features, but you want to _exactly_ know what is happening
where: plain TeX is small and easy to grasp (at least, when compared to
LaTeX or ConTeXt).

* LaTeX is what they call a "document preparation system", but that's a
lie.  LaTeX is a "scientific paper/monograph preparation system"; you
_may_ typeset a cookbook, a school test, or a software manual in LaTeX,
but it is a (sometimes small, sometimes big) pain.  It is just not the
best tool.  Of course, it flexible, extensible, even Turing complete, so
you can do everything - but it is sometimes like simulating recursion in
BASIC using arrays as a stack: possible, but no-one would like to do it.
The popularity of LaTeX caused, however, the situation when there is a
LaTeX package for everything (and sometimes even three of them, each
with different set of features and bugs...), so the pain is (usually)
not that big, but still sometimes writing stuff in LaTeX is not very
comfortable.

* ConTeXt is something much more universal than LaTeX - without the
scientific bias - but probably less stable than LaTeX, less documented
and with smaller userbase (but: smaller does not mean less active nor
less helpful!).  The flexibility of plain TeX, LaTeX and ConTeXt is
obviously similar (well, with ConTeXt actually bigger since the advent
of luatex), but it is sometimes _very_ different in terms of easiness
(and level of frustration), sometimes with LaTeX having more wtf per
minute and sometimes ConTeXt.  It seems, however, that Hans considered
much more special cases when writing ConTeXt, so many thing are more
natural in ConTeXt than in LaTeX (where even simplest things sometimes
need an external package - for example, changing the style of
enumerations).

> If I were choosing a TeX macro package at this point, I would definitely
>  look for one that kept semantics of basic TeX command sequences
> consistent with the intent expressed in the TeXbook... to avoid package
> lock-in, as well as to make the learning curve easier and to be able to
> use the resources of the whole TeX community.

As said - almost no-one uses plain TeX.  Both LaTeX and ConTeXt claim to
be "built on top of plain TeX", but in both cases it does _not_ mean
"saving the meaning of each and every plain TeX command" (and that is
clearly stated in both sources!).

> That being said, I appreciate the design goals of ConTeXt, including the
> desire to have independent controls for +/- italic, +/- serif, etc. I'm
> also amazed at the energy that Hans still devotes to answering questions
> on this mailing list, 18 years after ConTeXt was written! That's dedication.

That's right.  I would add one more point: if everyone called the
software of ConTeXt quality "beta", then Windows would be pre-alpha and
a typical GNU/Linux probably something between alpha and beta.

> Sorry if the above sounds too negative. After all, the TeXbook itself
> does not make the semantics of \rm obvious.

Well, it does, but _not_ in the context of changing sizes/styles/etc...

> However, once you dig deep enough it becomes clear that \rm does mean
> "switch to a non-italic typeface" in Plain TeX.

I'll stress it again: no.  In plain TeX, it means "switch to cmr10 at
10pt", full stop.

Greets

-- 
Marcin Borkowski (http://mbork.pl)

Walka trwa!
Nie przeciw ciału i krwi, lecz przeciw złym siłom.
Naszym ogniem Miłość Boga, naszym mieczem wierność Jego!
Walka trwa!
                        (Izaiash)
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Re: difference between TeX behavior and ConTeXt

[Hans Hagen]

Lars Huttar wrote:

> Interesting.
> As a newbie to typesetting, reading the TeXbook, I certainly wondered
> which "axes" Knuth meant 'roman' to refer to... he simply describes it
> as 'normal "roman"' and gives a visual example. So far, all I'd gathered
> was that it meant "not italic."

you should keep in mind that plain tex is not meant as general puspose 
macro package but as base under Don Knuths own book related styles

for instance, there is no general font system, just a bunch of 
definitions related to computer modern and math; also there is some math 
setup, some register management, some structure commands and a bit of 
tabular stuff

at that time i think that the general idea was that one would write a 
style for each book (or series) and that a plain like package can be 
used as basis

context is (like latex, lamstex, inrstex, amstex, ...) a more generic 
and configurable macro package

both methods (dedicated vs generic) have their (dis)advantages

> If it's designed not to do that in ConTeXt -- i.e. the ConTeXt designers
> decided to change the semantics of one of the basic control sequences in
> TeX, rather than merely providing a different one with new semantics --

not in tex, since tex itself has no macros defined, but in plain tex


Hans

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Re: difference between TeX behavior and ConTeXt

[Hans Hagen]

Marcin Borkowski wrote:

> Me not being an experienced programmer, but (some kind) of more or less
> experienced TeX user, I'd add the following.

...

makes a nice 'about tex systems' page for the wiki

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Re: difference between TeX behavior and ConTeXt

[Lars Huttar]

On 11/26/2008 2:41 AM, Marcin Borkowski wrote:
> Dnia Tue, Nov 25, 2008 at 10:30:51PM -0600, Lars Huttar napisał(a):
>> It makes sense for "italicness" and "serifity" to be independently
>> changeable.
>> What's discouraging to me as a entrant to the whole TeX world (but an
>> experienced programmer) is the (apparently undocumented) redefinition of
>> a well-established control sequence that used to mean "non-italic" to
>> mean something different (maybe "serif" -- I still don't know for sure).
> 
> Hi,
> 
> and welcome to the TeX world;).
> 
> Me not being an experienced programmer, but (some kind) of more or less
> experienced TeX user, I'd add the following.

I appreciate your time and the explanations, from an experienced TeX user.
(To all) please pardon the frustration apparent in my previous email,
from a TeX and especially ConTeXt newbie.

> It is probably true that plain TeX is weird and "incomplete" in a sense.
> What \rm means in plain TeX is: "switch to upright, serif font in 10pt
> size".

This is good to know.
However what I'm getting at is not just its concrete definition
(implementation) in Plain TeX, but its general intent.

The reason I ask that question is this: Knuth makes clear in TeXbook ch.
4 that \rm and other macros are intended to be redefined according to
the needs of the book section. Therefore \rm is not intended to remain
defined always specifically as "switch to upright, serif font in 10pt
size". But it is *not* intended that \rm be defined to mean "reduce the
left margin to the dimension provided by the following argument", or
even "switch to italic, serif font in 10pt size". Sure you could define
\rm to mean anything, but your end users would string you up.

Somewhere between those extremes is an intended consistency of meaning
for \rm. If it were not so, macro packages would be gibberish,
intelligible to the executing processor but intractable for humans.

My contention is that the intended "invariant" of \rm semantics,
communicated in TeXbook (e.g. exercise 4.2 and the bottom of p. 15), is
that of "not italic".

> [helpful orientation on the major macro packages snipped]

> (and level of frustration), sometimes with LaTeX having more wtf per
> minute 

I had not heard of that metric before. :-)

> That's right.  I would add one more point: if everyone called the
> software of ConTeXt quality "beta", then Windows would be pre-alpha and
> a typical GNU/Linux probably something between alpha and beta.

Except perhaps the documentation. I have yet to find a reference that
clearly describes what \rm is to do in ConTeXt. One responder pointed to
http://www.pragma-ade.com/general/manuals/cont-eni.pdf. The closest
thing to a definition of \rm there that I could find is on p. 111: "The
command \rm is used to switch to a roman/serif/regular style,..."
These three terms are not explicitly defined; they are given as names of
styles in an illustrative table above. One may apparently assume that
the meaning "serif" style here actually is intended to mean that the
typeface has serifs (not a trivial assumption: see 'regular'). However
the examples of serif/regular/roman in the illustrative table are also
all non-italic, and the word "regular" in typography usually (as far as
I can tell... please enlighten) means "upright" in contrast to italic.
Yet apparently \rm does not switch to "regular" (if that means or
includes "upright") in ConTeXt.

>> Sorry if the above sounds too negative. After all, the TeXbook itself
>> does not make the semantics of \rm obvious.
> 
> Well, it does, but _not_ in the context of changing sizes/styles/etc...

Again, I think we're talking about two different things: the original
macro definition in Plain TeX, vs. the communicated intended invariant
meaning over redefinitions of \rm in various "formats" (Knuth's term
which I take to mean macro packages or something like that).

>> However, once you dig deep enough it becomes clear that \rm does mean
>> "switch to a non-italic typeface" in Plain TeX.
> 
> I'll stress it again: no.  In plain TeX, it means "switch to cmr10 at
> 10pt", full stop.

See previous comment.

But even in plain TeX, "switch to cmr10 at 10pt" *does* include
switching to a non-italic typeface, which is what I meant here. I didn't
mean that in plain TeX \rm means *only* "switch to a non-italic
typeface." Sorry that wasn't clear.

And the jolt here with ConTeXt is that the meaning of \rm no longer
includes "switch to a non-italic typeface", and that this change is not
clearly documented.

Lars
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Re: difference between TeX behavior and ConTeXt

[Lars Huttar]

On 11/26/2008 7:43 AM, Lars Huttar wrote:
...
> and the word "regular" in typography usually (as far as
> I can tell... please enlighten) means "upright" in contrast to italic.

I now see that "regular" (apparently less often) can refer to weight:
"not bold or light". Still, the point remains.

Lars

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Re: difference between TeX behavior and ConTeXt

[Taco Hoekwater]

Lars Huttar wrote:
> 
> Except perhaps the documentation. I have yet to find a reference that
> clearly describes what \rm is to do in ConTeXt. One responder pointed to
> http://www.pragma-ade.com/general/manuals/cont-eni.pdf. The closest
> thing to a definition of \rm there that I could find is on p. 111: "The
> command \rm is used to switch to a roman/serif/regular style,..."

In his first reply to your message, Aditya posted the link to the new
manual chapter on "Typography". This chapter and the following one
"Fonts" are  planned to be the definitive answer to all questions
regarding fonts and font selection in ConTeXt.

If you believe the text could be improved even further beyond the
changes already made compared to the manual at Pragma ADE, please
tell us how (for sure, the meaning of the macro \rm is not going to
change!). We all want the manual to be as good as humanly possible,
but it is often quite hard to write at beginners' level when you
have advanced past that point yourself.

If you can find a good (or at least better) way to express what
\rm,\ss,\tt,\hw and \cg do compared to the current prose in
co-typography, please post it. Just keep in mind that the manual
has to remain independant, so texts that presuppose knowledge of
plain TeX and/or LaTeX are not acceptable except as a side/footnote.

Best wishes,
Taco
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Re: difference between TeX behavior and ConTeXt

[Lars Huttar]

On 11/26/2008 8:11 AM, Taco Hoekwater wrote:
> 
> Lars Huttar wrote:
>> Except perhaps the documentation. I have yet to find a reference that
>> clearly describes what \rm is to do in ConTeXt. One responder pointed to
>> http://www.pragma-ade.com/general/manuals/cont-eni.pdf. The closest
>> thing to a definition of \rm there that I could find is on p. 111: "The
>> command \rm is used to switch to a roman/serif/regular style,..."
> 
> In his first reply to your message, Aditya posted the link to the new
> manual chapter on "Typography". This chapter and the following one
> "Fonts" are  planned to be the definitive answer to all questions
> regarding fonts and font selection in ConTeXt.
> 
> If you believe the text could be improved even further beyond the
> changes already made compared to the manual at Pragma ADE, please
> tell us how (for sure, the meaning of the macro \rm is not going to
> change!).

Understood. :-)

> We all want the manual to be as good as humanly possible,
> but it is often quite hard to write at beginners' level when you
> have advanced past that point yourself.

Understood too.

> If you can find a good (or at least better) way to express what
> \rm,\ss,\tt,\hw and \cg do compared to the current prose in
> co-typography, please post it. Just keep in mind that the manual
> has to remain independant, so texts that presuppose knowledge of
> plain TeX and/or LaTeX are not acceptable except as a side/footnote.
> 

Thank you for being willing to take input to improve the documentation.

My #1 wish would be a reference section where \rm is described
unambiguously. So, for example, it would be very helpful to have it at
http://texshow.contextgarden.net/, since that is presented on the
ConTeXt garden wiki as a "ConTeXt command reference", "for all
user-commands that can be used in ConTeXt" (cc'ing Patrick Gundlach for
this reason). I see instructions there for commenting on a command, but
no way to request addition of a command.

In any case, an unambiguous description would be, instead of

	switch to a roman/serif/regular style [p. 3 of new manual chapter on
typography]

something like this:

	switch to a serif style

(if that's what \rm means in ConTeXt -- I still don't know for sure).

The word "regular" is ambiguous, as it commonly contrasts with "italic"
but sometimes with "bold". (And should I infer now that it sometimes
contrasts with sans-serif?)
Similarly, "roman" can have multiple meanings. To Knuth it meant
"non-italic".
As far as I'm aware, the term "serif style" is unambiguous. (But I'm not
a professional typographer.)

Table 1.2 lists "\rm   serif, regular, roman, rm" but does not say
whether all the words in the right column are supposed to be synonyms
for the same typeface attribute, or constitute a collection of different
attributes. It appears that some of them are the internal names of
styles? (the last one in each row), while others may be merely
descriptive. It would be helpful to have headers on the columns in this
table so that the reader knows what the data in each column indicates.
If everything in the right column is a command sequence in ConTeXt
(perhaps it's a defined font), it would be helpful to know that.
The first column could have the header "Command", matching the table
caption. The second column header depends on what the stuff in the
second column is. If it's intended to be merely a natural-language
description of what the command in the first column does, I think it
could be clarified as follows:

Command	/ Switch to style                / Internal style name
\rm     / serif                          / rm
\ss     / sans serif (a.k.a. "support")  / ss
\tt     / typewriter (monospaced)        / tt
\hw     / handwritten                    / hw
\cg     / calligraphic                   / cg
none    /                                / mm

I put the "Internal style name" column in there for completeness, but
it's not clear to me whether this is the meaning that was intended, nor
why a user would want to know about internal style names already... but
maybe that's just me.

Another place I would change it is p.4 under 1.3.1:
	"Examples of styles within a family are: ‘roman’, ‘sans serif’ and
‘teletype’"
could be clarified as
	"Examples of styles within a family are: ‘roman’ (which in ConTeXt
means ‘serif’), ‘sans serif’ and ‘teletype’".


Thanks...
your hard work and thick skin are appreciated. :-)

Lars

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Re: difference between TeX behavior and ConTeXt

[Taco Hoekwater]

Lars Huttar wrote:
> 
> something like this:
> 
> 	switch to a serif style
> 
> (if that's what \rm means in ConTeXt -- I still don't know for sure).

\rm in ConTeXT means: switch to the internal style group named "rm"
(and likewise for \ss -> "ss" etc.)

Whether "rm" points to a group of fonts that actually have serifs
attached to the glyph shapes depends totally on the specific typescript
that is being used in the document (usually they will, and I think all
the predefined typescripts are set up that way, but that is not a
requirement at all).

The basic idea is that the style "rm" switches to the font set used
for the main portion of the text. "ss" is the style for supporting
texts, like section heads and headers/footers. "tt" is useful for
fixed-width text, (this gets it own special group because it is very
often needed in manuals). "hw", and "cg" are variations for different
forms of supporting texts, these are rarely used.

Does it make more sense now?

Best wishes,
Taco


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Re: difference between TeX behavior and ConTeXt

[Lars Huttar]

On 11/27/2008 3:57 AM, Taco Hoekwater wrote:
> 
> Lars Huttar wrote:
>> something like this:
>>
>> 	switch to a serif style
>>
>> (if that's what \rm means in ConTeXt -- I still don't know for sure).
> 
> \rm in ConTeXT means: switch to the internal style group named "rm"
> (and likewise for \ss -> "ss" etc.)
> 
> Whether "rm" points to a group of fonts that actually have serifs
> attached to the glyph shapes depends totally on the specific typescript
> that is being used in the document (usually they will, and I think all
> the predefined typescripts are set up that way, but that is not a
> requirement at all).
> 
> The basic idea is that the style "rm" switches to the font set used
> for the main portion of the text. "ss" is the style for supporting
> texts, like section heads and headers/footers. "tt" is useful for
> fixed-width text, (this gets it own special group because it is very
> often needed in manuals). "hw", and "cg" are variations for different
> forms of supporting texts, these are rarely used.
> 
> Does it make more sense now?
> 

Thank you, that helps a lot. I understand now that \rm is more abstract
than I'd initially thought... more powerful but also harder to predict.
Nevertheless useful generalizations can be made (as you showed) that are
helpful in learning the system.

I think it would be worthwhile to explain that in the manual you are
writing (if it doesn't already... sorry, I'm on a tight deadline now and
can't recheck!)... that the style "rm" switches to the font set used for
the main portion of the text, which typically is a serif font. I think
it would also be helpful to note that this switch does not (normally?)
affect italicization, because some TeX-world users will be coming in
with wrong expectations regarding "rm" and italics.

Best wishes,
Lars
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