Re: safe way of writing arguments

[Hans Hagen <pragma@wxs.nl>]

Jano Kula wrote:
> Hans Hagen wrote:
>   
>> Jano Kula wrote:
>>     
>>> Hi!
>>>
>>> Is it safe to leave spare comma at the end of the key=value list or 
>>> other list of arguments?
>>>   
>>>       
>> in most cases it is ok
>>     
>>> It is not nice, but when adding/commenting arguments in readable way 
>>> (one per line) it's faster and while experimenting with parameters one 
>>> doesn't have to care about the last comma adding or removing it back and 
>>> forth, for example:
>>>
>>> \setuplayout[
>>> grid=yes,
>>> %header=0mm,
>>> footer=7mm,
>>> %footerdistance=10mm,
>>> %cutspace=12mm,
>>> ]
>>>   
>>>       
>> in this case a space after 12mm is not that problematic because layout 
>> are calculated in vertical mode and the 12 mm is used in assignments
>>     
>>> or
>>>
>>> \setuphead[
>>> chapter,
>>> section,
>>> %subsection,
>>> %subsubsection,
>>>   
>>>       
>> hm, here it can be troublesome unless i catch an empty case (not sure); 
>> if you run into troubles with such cases report it to the list and we 
>> can see if we can catch it
>>     
>>> ][
>>> textstyle=\ss,
>>> numberstyle=\ss,
>>> ]
>>>   
>>>       
>> Hans 
>>
>> -----------------------------------------------------------------
>>                                           Hans Hagen | PRAGMA ADE
>>               Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
>>      tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com
>>                                              | www.pragma-pod.nl
>> -----------------------------------------------------------------
>>     
>
> Thanks,
>
> I've found the example of the different behaviour, though the reason 
> isn't the comma, but the space after the command, I think. So even 
> writing parameters one-per-line (with space left behind = last one 
> without comma or percent sign) can be dangerous.
>
> %\setuphead[chapter][style=\bfd]        % works
> %\setuphead[chapter][style={\bfd}]      % works
> %\setuphead[chapter][style={\bfd} ]     % doesn't work
> %\setuphead[chapter][style={\bfd},]     % works
> \starttext
> \chapter{Test chapter}
> \stoptext
>
> This is not seriuos, I just want to find, how the things work.
>   
this is because the value of style is interpreted in its own special 
way; also, in

{xx}<space>

the become part of the value, and {\bfd} is ineffective due to grouping 
then

Hans

-----------------------------------------------------------------
                                          Hans Hagen | PRAGMA ADE
              Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
     tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com
                                             | www.pragma-pod.nl
-----------------------------------------------------------------