Process Last Item in \ForEach (forarray package)

Question

The following command of the forarray package

\ForEach{,}{\thislevelitem(\the\thislevelcount) : }}{x,y,z}

produces the output

x(1) : y(2) : z(3) :

I want to have the same output without the last ":".

The forarray package does not provide any command like \maxount to test if \thislevelcount == \maxcount. Surly I could test for the first item \thislevelcount == 0 but what to do if this cannot be done for some reason?

How can I process the last item separately if the number of items is variable/unknown?

Answer 1

You can cheat and prepend : to all the items except for the first

\documentclass{article}
\usepackage{forarray}
\begin{document}
  \ForEach{,}{\ifnum\thislevelcount=1\else : \fi\thislevelitem(\the\thislevelcount)}{x,y,z}
\end{document}

or you can use the totcount package to get the number of items in the array

\documentclass{article}
\usepackage{forarray}
\usepackage{totcount}
\begin{document}
  \newtotcounter{myarray}
  \ForEach{,}{\stepcounter{myarray}\thislevelitem(\the\thislevelcount)\ifnum\thislevelcount=\totvalue{myarray}\else : \fi}{x,y,z}    
\end{document}

Answer 2

You can also use the \indrisloop macro of the catoptions package.

\documentclass{article}
\usepackage{catoptions}
\begin{document}
\def\do#1{%
  #1(\indrisnr)\space\iflastindris\else:\space\fi
}
\indrisloop{x,y,x}\do
\end{document}

Answer 3

Similar to my comments in pgffor: Special treatment for last item in \foreach-list the other answers here provide solutions to accomplish the task at hand, but don't address the problem in the title of the question.

One way to detect the last list member and treat it differently is to count the number of members at the start of the list processing and compare that to \the\thislevelcount to know when we have come to the last one:

Notes:

• I am using the xstring package for the numerical comparison as I prefer it's syntax, but this could easily be adapted to not require that package.

References:

• Solution here is adapted form Array with Strings that are displayed on new line with indentation.
• What is the proper method of accessing a counter?

Code:

\documentclass{article}
\usepackage{forarray}
\usepackage{xstring}

\newcounter{TotalNumberOfListMembers}%
\newcommand{\SetTotalNumberOfListMembers}[1]{%
    \setcounter{TotalNumberOfListMembers}{0}%
    \ForEach{,}{\stepcounter{TotalNumberOfListMembers}}{#1}%
}%

\newcommand*{\ProcessListMembers}[1]{%
\SetTotalNumberOfListMembers{#1}
\ForEach{,}{%
    \thislevelitem(\the\thislevelcount)%
    \IfEq{\the\thislevelcount}{\the\value{TotalNumberOfListMembers}}{}{: }% 
}{#1}%
}%

\begin{document}
    \ProcessListMembers{x,y,z}
\end{document}