# [NTG-context] registers: setting pageleft parameter by index term

mf massifr at fastwebnet.it
Tue Apr 30 02:16:52 CEST 2019

Hello list, please consider this MWE:

\definenumber[p]
\setnumber[p][1]
\def\PageLeft{ p.~}
\def\TextCommand#1{\getnumber[p]
#1\doif{\rawcountervalue[p]}{2}{\def\PageLeft{ P.~}}\incrementnumber[p]}
\setupindex[n=1,pageleft=\PageLeft,pageright=,textcommand=\TextCommand]
\starttext
Foo\index{foo}.
\page
Bar\index{bar}.
\page
Baz\index{baz}.
\page
\placeindex
\stoptext

The pageleft parameter of \setupindex (\setupregister) is normally set
to " p.~", but it gets redefined to " P.~" for the second term in the
index ("baz").

Here i'm using a counter and i check when it is 2, but i'd like to check
if the term is "baz" (and i don't know how to do that test).

If you use deeptextcommand instead of textcommand, the pageleft
parameter can't be redefined.

The following variation compiles, but it does not work, because pageleft
is always " p.~":

\definenumber[p]
\setnumber[p][1]
\def\PageLeft{ p.~}
\def\TextCommand#1{\getnumber[p]
#1\doif{\rawcountervalue[p]}{2}{\def\PageLeft{ P.~}}\incrementnumber[p]}
\setupindex[n=1,pageleft=\PageLeft,pageright=,deeptextcommand=\TextCommand]
\starttext
Foo\index{foo}.
\page
Bar\index{bar}.
\page
Baz\index{baz}.
\page
\placeindex
\stoptext

In my setup i must use deeptextcommand, and i want to set the pageleft
and pageright parameters to a different value for some particular terms
of the index.

Since the argument passed to deeptextcommand is not the text of the term
(it's actually an id used to retrieve a much longer text), i can
discriminate the terms by their id, but i can't setup pageleft and
pageright accordingly from the command specified by deeptextcommand.

On the other hand, textcommand would let me set pageleft and pageright,
but its argument is not pure text, and i don't know how to get the id
from it.

How can i solve this problem?

Thanks,

Massimiliano