# [NTG-context] Testing the param value

Jan Tosovsky j.tosovsky at email.cz
Sun Jul 6 22:58:13 CEST 2014

On 2014-07-05 Wolfgang Schuster wrote:
> Am 05.07.2014 um 16:47 schrieb Jan Tosovsky:
>
> > I am hacking the context index entry rendering... ;-)
> > ... but I am stuck with a simple comparison
> >
> > How can I test the given entry if it equals to the specified one?
> >
> > The following code has no effect.
> >
> > \unexpanded\def\defaultregisterentry#1#2#3#4%
> > % #1:processor #2:internal #3:seeindex #4:word
> >  {\def\currentregisterpageindex{#2}%
> >   % start hacking
> >   \def\myword{#4}%
> >   \ifx\myword{My Primary}
> >      \column % do something
> >   \fi
> >   % stop hacking
> >   \strc_register_injector_process
> >   ...
> >
> > What is the proper syntax?
>
>
> This should be possible without hacks but without a example I can't
> provide more than a simple example code.
>
> \newconditional\IndexState
>
> \define[1]\IndexInternalCommand
>
> {\doifelse{#1}{MyPrimary}{\global\settrue\IndexState}{\global\setfalse\
> IndexState}#1}
>
> \define[1]\IndexCommand
>   {\setfalse\IndexState
>    \setbox\scratchbox\hbox{#1}%
>    \ifconditional\IndexState
>      \column
>    \fi
>    \box\nextbox}
>
> \setupregister
>   [index]
>   [    textcommand=\IndexCommand,
>    deeptextcommand=\IndexInternalCommand]
>

Thanks, it looks promising even I am quite lost in this logic :-)

Do I understand correctly that the IndexState is a global boolean which is
set either to true or false when deeptextcommand is processed and when
textcommand is called, it works with this pre-filled variable?

{\setfalse\IndexState % why this? A default value?
\setbox\scratchbox\hbox{#1}%
\box\nextbox} % what do these two do?

I am asking as #1 is consumed somehow and there is just a page reference in
the result index. But that break (\column) works correctly.

I've encountered mising words when comparing hashed params directly. Like if
they are read once, they are not available any more. This was the reason why
I used a helper 'myword' variable in my hack.

But I've just written that code analogically to some other conditions found
in the sources without proper knowledge what exactly it does.

Regards, Jan