pgfkeys: Different output depending on a keyword

Question

I need an output like

\cmd --> "S0" (output)

\cmd[] --> "S0" (output)

\cmd[map] ----> "S1 S2 S3" (output)

\cmd[map=true] ----> "S1 S2 S3" (output)

\cmd[map=false] ----> "S0" (output)

I looked here and here. How can I get a command with pgfkey for that?

\documentclass[a4paper]{article}
\usepackage{tikz}
\pgfkeys{/tikz/.cd,
    /map/.is family, 
    /map/.cd, %<-added /.cd 
     map/.is choice,
     map/.default=false,
     map/true/.code={S1 S2 S3}, 
     map/false/.code={S0}, 
}
\newcommand{\cmd}[1][]{%
%\tikzset{#1}%
\pgfkeys{map=true}
}
\begin{document}
Test:
\cmd[map]
\cmd[]
\end{document}

Rmano · Answer 1 · 2020-07-03T10:21:05.213

Comments in the code...

\documentclass[a4paper]{article}
\usepackage{pgfkeys} %no need to full-load tikz
\pgfkeys{%/tikz/.cd, you want your top-family, no?
     % /map/.is family,
     % /map/.cd, %<-added .cd why?
     /map/.is choice,
     % /map/.default=false, % not useful in choices, you have to call one of them anyway
     /map/true/.code={S1 S2 S3},
     /map/false/.code={S0},
}
\newcommand{\cmd}[1][false]{%
\pgfkeys{/map=#1}
}
\begin{document}
Test:
\cmd[true]
\cmd % if you use \cmd[] you ends with /map= which is not a choice
\end{document}

Notice that true and false are fully customizable here --- you can call them whatever you want, they're just names.

Anyway, I would rather separate the key management and the code. So I will

define a top family for my application
add a specific function to set keys in this family
use the keys to switch/set things

Like this:

\documentclass[a4paper]{article}
\usepackage{pgfkeys}
\newif\ifdomap\domapfalse
\pgfkeys{
     /cis/.is family, /cis/.cd,
     map/.is choice,
     map/true/.code={\domaptrue},
     map/false/.code={\domapfalse},
}
\newcommand{\cisset}[1]{\pgfkeys{/cis/.cd, #1}}
\newcommand{\cmd}[1][]{%
    \begingroup % change the keys locally
    \cisset{#1}%
    \ifdomap
        S1 S2 S3
    \else
        S0
    \fi
    \endgroup
}
\begin{document}
Test:
\par No map: \cmd
\par Map (locally): \cmd[map=true]
\par No map: \cmd
\par Set globally to true \cisset{map=true}
\par Map: \cmd
\par No map (locally):  \cmd[map=false]
\par Set globally to false \cisset{map=false}
\par No map: \cmd
\end{document}

This is a bit low level, you can use xifthen package if you are addressing just LaTeX.

If you want a simple map key, you just do not use the is choice handler:

\documentclass[a4paper]{article}
\usepackage{pgfkeys}
\newif\ifdomap
\pgfkeys{
     /cis/.is family, /cis/.cd,
     map/.code={\domaptrue},
     no map/.code={\domapfalse},
     no map % set the default
}
\newcommand{\cisset}[1]{\pgfkeys{/cis/.cd, #1}}
\newcommand{\cmd}[1][]{%
    \begingroup % change the keys locally
    \cisset{#1}%
    \ifdomap
        S1 S2 S3
    \else
        S0
    \fi
    \endgroup
}
\begin{document}
Test:
\par No map: \cmd
\par Map (locally): \cmd[map]
\par No map: \cmd
\par Set globally to true \cisset{map}
\par Map: \cmd
\par No map (locally):  \cmd[no map]
\par Set globally to false \cisset{no map}
\par No map: \cmd
\end{document}

And finally, this allows to have both the map switch and a map=... switch, similar to lot of options in TikZ. This uses an auxiliary key and a style with an (optional, thanks to the .default) argument.

\documentclass[a4paper]{article}
\usepackage{pgfkeys}
\newif\ifdomap
\pgfkeys{
     /cis/.is family, /cis/.cd,
     domap/.is choice,
     domap/false/.code={\domapfalse},
     domap/true/.code={\domaptrue},
     map/.style={domap=#1},
     map/.default=true, % for this key
     domap=false, % global default
}
\newcommand{\cisset}[1]{\pgfkeys{/cis/.cd, #1}}
\newcommand{\cmd}[1][]{%
    \begingroup % change the keys locally
    \cisset{#1}%
    \ifdomap
        S1 S2 S3
    \else
        S0
    \fi
    \endgroup
}
\begin{document}
Test:
\par No map: \cmd
\par Map (locally): \cmd[map]
\par Map (locally): \cmd[map=true]
\par No map (locally, forced): \cmd[map=false]
\par No map (default): \cmd
\par Set globally to true \cisset{map} % or \cisset{map=true}
\par Map: \cmd
\par No map (locally):  \cmd[map=false]
\par Set globally to false \cisset{map=false}
\par No map: \cmd
\end{document}

A very nice answer is also https://tex.stackexchange.com/a/114017/38080

Ahh, good. Is it possible to create that like \cmd[map] or \cmd[] = \cmd[map=false]? Because, there should come lots of other parameters / keys, so "\cmd[true]" is not a good syntax. — cis, Jul 03 '20 at 08:25
@cis like this? This is basically how I use the keys in circuitikz. There is even a special key handler to automatically associate to an if, but I find this easier to read. — Rmano, Jul 03 '20 at 08:52
I have two problems here:

\cmd[map] alone seems not to work.

But fundamentally I wonder why this seems not to be possible with "plain pgfkeys syntax" — cis, Jul 03 '20 at 09:23
Because: It is clear that this is an abstract, simplified MWE from me. I don't just want to write "S1 S2 S3". I can hardly list the 17 lines that are hidden behind "S2" in the "MWE". That I basically need numerous other keys - that means: If this is only possible in such a complicated way, I cannot use it. But it has to be easier. Mmhhh ...
I should basically understand this pgfkey syntax. Then I could do the rest alone. But, as I said, if this is only possible with all possible other "plain TeX" methods, then I can not deduce from it. — cis, Jul 03 '20 at 09:23

pgfkeys: Different output depending on a keyword

1 Answers1