From: "Wolfgang Schuster" <schuster.wolfgang@gmail.com>
Sent: Monday, April 2, 2018 2:41 PM
To: "mailing list for ConTeXt users" <ntg-context@ntg.nl>
Subject: Re: [NTG-context] Questions about \starttext  

Tomas Hala

20. März 2018 um 12:43

Hi all,

doing some tests I discovered two interesting facts.

The first is that commands \starttext and \stoptext do not behave as a group.

Minimal example (tested on TL2015, TL2016, TL2017, current CTX from the Garden):

\starttext
text
\starttext
\bf text
\stoptext
text % this text is in bold, too.
\stoptext

Is this the expected behaviour, or not?

Opening a group with \starttext makes no sense because there is nothing after \stoptext.

The possibility to nest \starttext is necessary when you \startproduct etc. where components
can be be documents on its own and this means \startcomponent includes \starttext in its
definition.
 

The second interesting thing is that the unbalanced document is compiled without protests:

Minimal example #1 (tested on TL2015, TL2016, TL2017, current CTX from the Garden):

\starttext
text % in this case, the "text" is shipped out

Take a look at the command line when you process a file and you should see something like this:

mtx-context     | run 1: luatex --fmt="[...]/cont-en" --jobname="test" [...] --c:input="./test.tex" [...] "cont-yes.mkiv"


As you can see the luatex engine processes the file cont-yes.mkiv and not your document
which put as argument to context. Your document is just read by cont-yes.mkiv and at the
end of the document ConTeXt inserts an extra \stoptext which is ignored when your document
is valid (equal number of \starttext and \stoptext).
 

Minimal example #2 (tested on TL2015, TL2016, TL2017, current CTX from the Garden):

text % in this case, the "text" is not shipped out
\stoptext

The reason why no text appears is that ConTeXt doesn’t load the default fonts
untill \starttext. The reason for this is to is a gain in speed and you save resources.

You can test this by adding \setupbodyfont[modern] at the begin of your example.


Wolfgang