Modifying a Makeindex Algorithm to Remove Page Numbers on a Selective Basis Only

Question

I have extracted the following code from an answer in Remove page number from index entries

which removes the page number from each index entry:

\documentclass{article}
\usepackage{xcolor}
\usepackage{imakeidx}
\makeindex[program=makeindex,options=-s mystyle.ist]
\usepackage{letltxmacro}
\usepackage{filecontents}
\makeatletter
\let\mygobble@gobble
\LetLtxMacro\OldIndex\index
\renewcommand{\index}[1]{\OldIndex{#1|mygobble}} 
\makeatother
\begin{filecontents}{mystyle.ist}
quote '+'
delim_0 " "
delim_1 " "
delim_2 " "
delim_n " "
\end{filecontents}
\begin{document}
\LARGE
Test\index{foo}
\index{bar}
\printindex
\end{document}

which produces the index output:

I thought, perhaps, there might be a way to modify the above code so that the page number might be "gobbled" on a selective basis instead of globally; more specifically, I attempted to define an index command, say, \index1 that would remove the page number if used---and, if using \index, the page number would be retained.

However, I was unsuccessful in my various attempts.

QUESTION: If possible, how might one modify the above code so that the entry page number may be removed on a selective (and not global) basis?

Thank you.

Answer 1

Use \newcommand{\indexi}[1]{\OldIndex{#1|mygobble}} (numbers are not allowed in commands names)

\documentclass{article}
\usepackage{xcolor}
\usepackage{imakeidx}
\makeindex[program=makeindex,options=-s mystyle.ist]
\usepackage{letltxmacro}
\usepackage{filecontents}
\makeatletter
\let\mygobble@gobble
\LetLtxMacro\OldIndex\index
\newcommand{\indexi}[1]{\OldIndex{#1|mygobble}} % changed <<<<<<<<
\makeatother
\begin{filecontents}{mystyle.ist}
    quote '+'
    delim_0 " "
    delim_1 " "
    delim_2 " "
    delim_n " "
\end{filecontents}
\begin{document}
    \LARGE
Test\indexi{foo}  % no page number
\index{bar}
\printindex

\end{document}