Wie kann ich Folgendes in Latex implementieren: Ich möchte eine vordefinierte Variable haben (in der Präambel), nennen wir sie A.
Dann wünsche ich mir einen Befehl wie
\TwoTexts{Text1}{Text2}
das wird folgendermaßen umgesetzt: wenn A=1, dann wird Text1 angezeigt, wenn A=2, dann wird Text2 angezeigt.
Irgendwelche Ideen? Danke!
Antwort1
Hier ist eine Version mit Makro \Amacrooder einem Zähler namens acntr. Ich persönlich bevorzuge die Zählerversion, da dabei keine Neudefinition von \Amacroif erforderlich ist.
Der Test für 1oder sonst erfolgt mit\ifnum...\fi
Hier bin ich davon ausgegangen, dass jeder andere Wert als 1zu verzweigt Text2.
\documentclass{article}
\newcommand{\Amacro}{1}
\newcommand{\TwoTexts}[2]{%
\ifnum\Amacro=1\relax%
#1%
\else
#2%
\fi
}
\newcounter{acntr}
\newcommand{\TwoTextsImproved}[2]{%
\ifnum\value{acntr}=1\relax
#1%
\else
#2%
\fi
}
\begin{document}
\setcounter{acntr}{1}
\TwoTexts{You should see this}{Nope, not this}
\renewcommand{\Amacro}{2}
\TwoTexts{You should see this}{Nope, this is it}
\TwoTextsImproved{You should see this}{Nope, not this}
\stepcounter{acntr}
\TwoTextsImproved{You should see this}{Nope, this is it}
\end{document}
Antwort2
Um Probleme mit unsymmetrischen \if.... \else.. zu vermeiden, \fiwürde ich den Trick in Bezug auf \Firstoftwo/ tun \Secondoftwo:
\documentclass{article}
\newcommand\Firstoftwo[2]{#1}%
\newcommand\Secondoftwo[2]{#2}%
\newcommand\Amacro{1}%
\newcommand\setAmacro[1]{\renewcommand\Amacro{#1}}%
\newcommand{\TwoTexts}{%
\ifnum\Amacro>1 %
\expandafter\Secondoftwo
\else
\expandafter\Firstoftwo
\fi
}
\begin{document}
\setAmacro{-3}
\texttt{\string\Amacro} is \Amacro.\\
\TwoTexts{Text in case the value in \texttt{\string\Amacro} is smaller than 1 or equal to 1}%
{Text in case the value in \texttt{\string\Amacro} is larger than 1}%
\setAmacro{0}
\texttt{\string\Amacro} is \Amacro.\\
\TwoTexts{Text in case the value in \texttt{\string\Amacro} is smaller than 1 or equal to 1}%
{Text in case the value in \texttt{\string\Amacro} is larger than 1}%
\setAmacro{1}
\texttt{\string\Amacro} is \Amacro.\\
\TwoTexts{Text in case the value in \texttt{\string\Amacro} is smaller than 1 or equal to 1}%
{Text in case the value in \texttt{\string\Amacro} is larger than 1}%
\setAmacro{2}
\texttt{\string\Amacro} is \Amacro.\\
\TwoTexts{Text in case the value in \texttt{\string\Amacro} is smaller than 1 or equal to 1}%
{Text in case the value in \texttt{\string\Amacro} is larger than 1}%
\setAmacro{17}
\texttt{\string\Amacro} is \Amacro.\\
\TwoTexts{Text in case the value in \texttt{\string\Amacro} is smaller than 1 or equal to 1}%
{Text in case the value in \texttt{\string\Amacro} is larger than 1}%
\end{document}
Übrigens: Vor einigen Jahren habe ich eine Routine geschrieben \UD@KeepKthOfLArguments, mit der Sie aus einer beliebigen Menge von unbegrenzten Argumenten ein beliebiges unbegrenztes Argument auswählen können, das – aufgrund der Rekursion – nicht an die 9-Argument-Begrenzung gebunden ist, die der Makroprogrammierung in TeX normalerweise auferlegt wird.
Sie können diese Routine zum Erstellen einer anderen Routine verwenden \choosetext, die nicht begrenzte Argumente mit Textphrasen auswählt, abhängig vom numerischen Wert in einer Variablen/einem Platzhalter/einem Makro/ \counteinem Register/was auch immer.
\documentclass{article}
\makeatletter
%%=========================================================================
%% Paraphernalia:
%% \UD@firstoftwo, \UD@secondoftwo, \UD@PassFirstToSecond
%%.........................................................................
\newcommand\UD@firstoftwo[2]{#1}%
\newcommand\UD@secondoftwo[2]{#2}%
\newcommand\UD@PassFirstToSecond[2]{#2{#1}}%
%%-------------------------------------------------------------------------
%% Check whether argument is empty:
%%.........................................................................
%% \UD@CheckWhetherNull{<Argument which is to be checked>}%
%% {<Tokens to be delivered in case that argument
%% which is to be checked is empty>}%
%% {<Tokens to be delivered in case that argument
%% which is to be checked is not empty>}%
%%
%% The gist of this macro comes from Robert R. Schneck's \ifempty-macro:
%% <https://groups.google.com/forum/#!original/comp.text.tex/kuOEIQIrElc/lUg37FmhA74J>
%%
%% A concern in his posting is that the argument is hit with \string
%% after some expansions which in edge cases might result in unbalancing
%% surrounding \if..\fi-constructs if the macro is used inside of such
%% \if..\fi-constructs.
%%
%% That challenging concern sickened me. ;-)
%%
%% Therefore I decided to implerment a variant where this cannot happen
%% as expansion is forced by \romannumeral:
%%
%% After the first expansion-step, \string is not applied yet.
%% After the second expansion-step, any possibly disturbing remainders
%% are already removed due to \romannumeral-expansion.
%%
%% No eTeX- or whatsoever extensions. No \if.. .Only \romannumeral,
%% digit 0, space token for terminating \romannumeral-expansion,
%% \string, \expandafter, \UD@firstoftwo, \UD@secondoftwo, {, }.
%%
%% May 20, 2016
%%
%% Ulrich Diez (e-mail: [email protected])
%%
\newcommand\UD@CheckWhetherNull[1]{%
\romannumeral0\expandafter\UD@secondoftwo\string{\expandafter
\UD@secondoftwo\expandafter{\expandafter{\string#1}\expandafter
\UD@secondoftwo\string}\expandafter\UD@firstoftwo\expandafter{\expandafter
\UD@secondoftwo\string}\expandafter\expandafter\UD@firstoftwo{ }{}%
\UD@secondoftwo}{\expandafter\expandafter\UD@firstoftwo{ }{}\UD@firstoftwo}%
}%
%%-------------------------------------------------------------------------
%% Keep only the K-th of L consecutive undelimited arguments.
%% ( IF K < 1 OR K > L just remove L consecutive undelimited arguments. )
%%.........................................................................
%% \UD@KeepKthOfLArguments{<integer number K>}%
%% {<integer number L>}%
%% {<Tokens to insert before K-th argument>}%
%% <L consecutive undelimited arguments>
%%
%% If K >= 1 and K <= L yields:
%% <Tokens to insert before K-th argument><K-th undelimited argument>
%% If K < 1 or K > L
%% (-> there is no K-th argument in the set
%% of <L consecutive undelimited arguments> )
%% yields:
%% <Tokens to insert before K-th argument>
%%
%% Examples:
%%
%% X\UD@KeepKthOfLArguments{3}{7}{<Tokens to insert>}{A}{B}{C}{D}{E}{F}{G}X
%% yields: X<Tokens to insert>CX
%%
%% X\UD@KeepKthOfLArguments{5}{2}{<Tokens to insert>}{A}{B}X
%% yields X<Tokens to insert>X
%%
%% X\UD@KeepKthOfLArguments{0}{2}{<Tokens to insert>}{A}{B}X
%% yields X<Tokens to insert>X
%%
%% X\romannumeral0%
%% \UD@KeepKthOfLArguments{3}{7}{ <Tokens to insert>}{A}{B}{C}{D}{E}{F}{G}X
%% yields: X\romannumeral0 <Tokens to insert>CX
%% yields: X<Tokens to insert>CX
%% In case of embedding the whole thing in other expansion-contexts,
%% you need to have "hit" \romannumeral by only one \expandafter-chain for
%% obtaining the result...
%%
%% January 17, 2005
%%
%% Ulrich Diez (e-mail: [email protected])
%%
\newcommand\UD@KeepKthOfLArguments[2]{%
\expandafter\UD@KeepKthOfLArgumentsA
\expandafter{\romannumeral\number\number#1 000\expandafter}%
\expandafter{\romannumeral\number\number#2 000}%
}%
\newcommand\UD@KeepKthOfLArgumentsA[3]{%
\UD@CheckWhetherNull{#1}{%
\UD@RemoveNArguments{#2}{#3}{}%
}{%
\expandafter\UD@PassFirstToSecond
\expandafter{%
\UD@firstoftwo{}#1}{\UD@KeepKthOfLArgumentsB{#1}{#2}}{#2}{#3}%
}%
}%
\newcommand\UD@KeepKthOfLArgumentsB[5]{%
\UD@CheckWhetherNull{#1}{%
\UD@RemoveNArguments{#3}{\UD@RemoveNArguments{#2}{#5}}{}%
}{%
\UD@CheckWhetherNull{#2}{%
\UD@RemoveNArguments{#4}{#5}{}%
}{%
\expandafter\UD@PassFirstToSecond
\expandafter{%
\UD@firstoftwo{}#2}{\expandafter\UD@KeepKthOfLArgumentsB
\expandafter{%
\UD@firstoftwo{}#1}}{#3}{#4}{#5}%
}%
}%
}%
\newcommand\UD@RemoveNArguments[3]{%
\UD@CheckWhetherNull{#1}{#2#3}{%
\UD@firstoftwo{%
\expandafter\UD@RemoveNArguments
\expandafter{\UD@firstoftwo{}#1}{#2}{#3}%
}%
}%
}%
%%-------------------------------------------------------------------------
%% A demo-routine:
%%
%% \choosetext{<number>}%
%% {<Text in case number < 1>}%
%% {<Text in case number = 1>}%
%% {<Text in case number = 2>}%
%% {<Text in case number = 3>}%
%% {<Text in case number = 4>}%
%% {<Text in case number = 5>}%
%% {<Text in case number = 6>}%
%% {<Text in case number = 7>}%
%% {<Text in case number = 8>}%
%% {<Text in case number = 9>}%
%% {<Text in case number = 10>}%
%% {<Text in case number = 11>}%
%% {<Text in case number = 12>}%
%% {<Text in case number = 13>}%
%% {<Text in case number = 14>}%
%% {<Text in case number > 14>}%
%%
%% The <number>-argument can hold anything that _expands_ to the components
%% of a quantity that is subsumable under the term <number> which is
%% explained in Donald E. Knuth's The TeXbook, Chapter 24: Summary of
%% Vertical Mode.
%%
%% Therefore <number> can as well be a macro-token expanding to a digit-
%% sequence, or a \the-call to a \count-register.
%%
%% January 24, 2017
%%
%% Ulrich Diez (e-mail: [email protected])
%%
%%.........................................................................
\newcommand\choosetext[1]{%
\romannumeral0%
\UD@KeepKthOfLArguments{\ifcase\expandafter\UD@firstoftwo
\expandafter{\number\ifnum#1<1 0\else#1\fi}{} %
1\or2\or3\or4\or5\or6\or7\or8\or
9\or10\or11\or12\or13\or14\or15\else16\fi}%
{16}%
{ }%
}%
%%-------------------------------------------------------------------------
%% A "variable" \Amacro and the routine \setAmacro for setting it's value.
%%.........................................................................
\newcommand\Amacro{1}%
\newcommand\setAmacro[1]{\renewcommand\Amacro{#1}}%
\makeatother
\begin{document}
The \verb|<number>|-argument of \verb|\choosetext| can hold anything that
expands to the components of a quantity that is subsumable under the term
\verb|<number>| which is explained in Donald E. Knuth's The TeXbook,
Chapter 24: Summary of Vertical Mode.
\bigskip
Thus the \verb|<number>|-argument of \verb|\choosetext| can hold a sequence
of digits, e.g., the digit \verb|5|:
\bigskip
\choosetext{5}{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\bigskip
The \verb|<number>|-argument of \verb|\choosetext| can as well hold a
macro-token which serves as variable/placeholder for numerical values.
\bigskip
\setAmacro{17}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{15}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{14}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{13}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{12}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{11}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{10}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{9}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{8}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{7}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{6}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{5}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{4}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{3}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{2}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{1}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{0}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{-1}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\end{document}
Antwort3
Wie Adein"Variable") eine Konstante ist, können Sie \TwoTextswie folgt definieren:
\newcommand\TwoTexts[2]{#1} % case A = 1
% \newcommand\TwoTexts[2]{#2} % case A = 2
Um den Wert auszuwählen A, heben Sie die Kommentierung der richtigen Zeile auf.
Antwort4
Ich habe gerade meine \choosetext-Routine erweitert vonhttps://tex.stackexchange.com/a/350169/118714. Nun können Sie die Unter- und Obergrenze für den Wertebereich der Variablen Zahl angeben. Mithilfe des bigintcalc-Pakets von Heiko Oberdiek berechnet die Routine die Anzahl der zu verarbeitenden unbegrenzten Argumente und wählt automatisch das richtige Argument aus.
\documentclass{article}
\usepackage{bigintcalc}
\makeatletter
%%=========================================================================
%% Paraphernalia:
%% \UD@firstoftwo, \UD@secondoftwo, \UD@PassFirstToSecond
%%.........................................................................
\newcommand\UD@firstoftwo[2]{#1}%
\newcommand\UD@secondoftwo[2]{#2}%
\newcommand\UD@PassFirstToSecond[2]{#2{#1}}%
%%-------------------------------------------------------------------------
%% Check whether argument is empty:
%%.........................................................................
%% \UD@CheckWhetherNull{<Argument which is to be checked>}%
%% {<Tokens to be delivered in case that argument
%% which is to be checked is empty>}%
%% {<Tokens to be delivered in case that argument
%% which is to be checked is not empty>}%
%%
%% The gist of this macro comes from Robert R. Schneck's \ifempty-macro:
%% <https://groups.google.com/forum/#!original/comp.text.tex/kuOEIQIrElc/lUg37FmhA74J>
%%
%% A concern in his posting is that the argument is hit with \string
%% after some expansions which in edge cases might result in unbalancing
%% surrounding \if..\fi-constructs if the macro is used inside of such
%% \if..\fi-constructs.
%%
%% That challenging concern sickened me. ;-)
%%
%% Therefore I decided to implerment a variant where this cannot happen
%% as expansion is forced by \romannumeral:
%%
%% After the first expansion-step, \string is not applied yet.
%% After the second expansion-step, any possibly disturbing remainders
%% are already removed due to \romannumeral-expansion.
%%
%% No eTeX- or whatsoever extensions. No \if.. .Only \romannumeral,
%% digit 0, space token for terminating \romannumeral-expansion,
%% \string, \expandafter, \UD@firstoftwo, \UD@secondoftwo, {, }.
%%
%% May 20, 2016
%%
%% Ulrich Diez (e-mail: [email protected])
%%
\newcommand\UD@CheckWhetherNull[1]{%
\romannumeral0\expandafter\UD@secondoftwo\string{\expandafter
\UD@secondoftwo\expandafter{\expandafter{\string#1}\expandafter
\UD@secondoftwo\string}\expandafter\UD@firstoftwo\expandafter{\expandafter
\UD@secondoftwo\string}\expandafter\expandafter\UD@firstoftwo{ }{}%
\UD@secondoftwo}{\expandafter\expandafter\UD@firstoftwo{ }{}\UD@firstoftwo}%
}%
%%-------------------------------------------------------------------------
%% Keep only the K-th of L consecutive undelimited arguments.
%% ( IF K < 1 OR K > L just remove L consecutive undelimited arguments. )
%%.........................................................................
%% \UD@KeepKthOfLArguments{<integer number K>}%
%% {<integer number L>}%
%% {<Tokens to insert before K-th argument>}%
%% <L consecutive undelimited arguments>
%%
%% If K >= 1 and K <= L yields:
%% <Tokens to insert before K-th argument><K-th undelimited argument>
%% If K < 1 or K > L
%% (-> there is no K-th argument in the set
%% of <L consecutive undelimited arguments> )
%% yields:
%% <Tokens to insert before K-th argument>
%%
%% Examples:
%%
%% X\UD@KeepKthOfLArguments{3}{7}{<Tokens to insert>}{A}{B}{C}{D}{E}{F}{G}X
%% yields: X<Tokens to insert>CX
%%
%% X\UD@KeepKthOfLArguments{5}{2}{<Tokens to insert>}{A}{B}X
%% yields X<Tokens to insert>X
%%
%% X\UD@KeepKthOfLArguments{0}{2}{<Tokens to insert>}{A}{B}X
%% yields X<Tokens to insert>X
%%
%% X\romannumeral0%
%% \UD@KeepKthOfLArguments{3}{7}{ <Tokens to insert>}{A}{B}{C}{D}{E}{F}{G}X
%% yields: X\romannumeral0 <Tokens to insert>CX
%% yields: X<Tokens to insert>CX
%% In case of embedding the whole thing in other expansion-contexts,
%% you need to have "hit" \romannumeral by only one \expandafter-chain for
%% obtaining the result...
%%
%% January 17, 2005
%%
%% Ulrich Diez (e-mail: [email protected])
%%
\newcommand\UD@KeepKthOfLArguments[2]{%
\expandafter\UD@KeepKthOfLArgumentsA
\expandafter{\romannumeral\number\number#1 000\expandafter}%
\expandafter{\romannumeral\number\number#2 000}%
}%
\newcommand\UD@KeepKthOfLArgumentsA[3]{%
\UD@CheckWhetherNull{#1}{%
\UD@RemoveNArguments{#2}{#3}{}%
}{%
\expandafter\UD@PassFirstToSecond
\expandafter{%
\UD@firstoftwo{}#1}{\UD@KeepKthOfLArgumentsB{#1}{#2}}{#2}{#3}%
}%
}%
\newcommand\UD@KeepKthOfLArgumentsB[5]{%
\UD@CheckWhetherNull{#1}{%
\UD@RemoveNArguments{#3}{\UD@RemoveNArguments{#2}{#5}}{}%
}{%
\UD@CheckWhetherNull{#2}{%
\UD@RemoveNArguments{#4}{#5}{}%
}{%
\expandafter\UD@PassFirstToSecond
\expandafter{%
\UD@firstoftwo{}#2}{\expandafter\UD@KeepKthOfLArgumentsB
\expandafter{%
\UD@firstoftwo{}#1}}{#3}{#4}{#5}%
}%
}%
}%
\newcommand\UD@RemoveNArguments[3]{%
\UD@CheckWhetherNull{#1}{#2#3}{%
\UD@firstoftwo{%
\expandafter\UD@RemoveNArguments
\expandafter{\UD@firstoftwo{}#1}{#2}{#3}%
}%
}%
}%
%%-------------------------------------------------------------------------
%% \UD@incrementloop{<lower bound>}%
%% {<upper bound>}%
%% {<count start>}%
%% {<tokens to prepend in front of each number except last number>}%
%% {<tokens to prepend in front of last number>}%
%% {<tokens to prepend at the begnning>}%
%% {<tokens to append at the end>}%
%%
%% Examples:
%% \UD@incrementloop{3}{7}{2}{<Before All>}{<Before Number>}{<Before Last Number>}{<After Last Numbe>r}
%%
%% -> The range 3..7 contains 7-3+1 consecutive integeral numbers/elements
%% = 5 consecutive integeral numbers/elements.
%% -> Gathering 5 consecutive integeral numbers/elements starting with
%% number/element 2 yields the numbers/elements 2,3,4,5,6.
%% (You can gather them by iteratively decrementing from 7-3=4 until
%% reaching -1 while within each iteration before reaching -1
%% "spitting out" a value and incrementing that value, starting
%% with value=2.)
%%
%% -> <Before All><Before Number>2<Before Number>3<Before Number>4<Before Number>5<Before Last Number>6<After Last Number>
%%
%% ,i.e., with
%% <Before All>=\ifcase[<number>] 1} and
%% <Before Number>=\or and
%% <Before Last Number>=\else and
%% <After Last Number>=\fi
%% yields:
%%
%% \UD@incrementloop{3}{7}{2}{\ifcase[<number>] 1}{\or}{\else}{\fi}
%% ->
%% \ifcase[<number>] 1\or2\or3\or4\or5\else6\fi
%%
\newcommand\UD@incrementloop[3]{%
\romannumeral0%
\expandafter\UD@PassFirstToSecond
\expandafter{\number#3}{%
\expandafter\expandafter\expandafter\UD@PassFirstToSecond
\expandafter\expandafter\expandafter{\bigintcalcSub{\number#2}{\number#1}}%
{\UD@@incrementloop}{}%
}%
}%
\newcommand\UD@@incrementloop[7]{%
\ifnum\bigintcalcCmp{0}{#1}=-1 %
\expandafter\UD@secondoftwo
\else
\expandafter\UD@firstoftwo
\fi
{%
\ifnum\bigintcalcCmp{0}{#1}=1 %
\expandafter\UD@secondoftwo
\else
\expandafter\UD@firstoftwo
\fi
{ #4#2#6#3#7}%
{ #4#2#7}%
}{%
\expandafter\expandafter\expandafter\UD@PassFirstToSecond
\expandafter\expandafter\expandafter{\bigintcalcInc{#3}}%
{\expandafter\expandafter\expandafter\UD@@incrementloop
\expandafter\expandafter\expandafter{\bigintcalcDec{#1}}%
{#2#5#3}}{#4}{#5}{#6}{#7}%
}%
}%
%%-------------------------------------------------------------------------
%% A demo-routine:
%%
%% \choosetext{<number from variable>}%
%% {<number denoting lower bound>}%
%% {<number denoting upper bound>}%
%% {<Text in case <number from variable> is smaller than <number denoting lower bound> >}%
%% {<Text in case <number from variable> = <number denoting lower bound> >}%
%% {<Text in case <number from variable> = <number denoting lower bound>+1 >}%
%% {<Text in case <number from variable> = <number denoting lower bound>+2 >}%
%% ...
%% {<Text in case <number from variable> = <number denoting lower bound>+K >
%% ...
%% {<Text in case <number from variable> = <number denoting upper bound>-2 >}%
%% {<Text in case <number from variable> = <number denoting upper bound>-1 >}%
%% {<Text in case <number from variable> = <number denoting upper bound> >}%
%% {<Text in case <number from variable> is larger than <number denoting upper bound> >}%
%%
%% The <number...>-arguments can hold anything that _expands_ to the components
%% of a quantity that is subsumable under the term <number> which is
%% explained in Donald E. Knuth's The TeXbook, Chapter 24: Summary of
%% Vertical Mode.
%%
%% Therefore the <number...>-arguments can as well be a macro-tokens expanding
%% to a digit-sequences, or \the-calls to \count-registers.
%%
%% Due to \romannumeral-expansion the result is delivered within two
%% expansion-steps.
%%
%% January 24, 2017
%%
%% Ulrich Diez (e-mail: [email protected])
%%
%%.........................................................................
\newcommand\choosetext[3]{%
\romannumeral0%
\UD@KeepKthOfLArguments{%
\UD@incrementloop{2}%
{\bigintcalcAdd{\bigintcalcSub{\number#3}{\number#2}}{3}}%
{2}%
{%
\ifcase\expandafter\UD@firstoftwo\expandafter{%
\number
\ifnum\bigintcalcCmp{%
\bigintcalcSub{\number#1}{\number#2}%
}{0}<0 %
\expandafter\UD@firstoftwo
\else
\expandafter\UD@secondoftwo
\fi
{0}{%
\bigintcalcAdd
{\bigintcalcSub{\number#1}{\number#2}}%
{1}%
}%
}{} 1%
}%
{\or}%
{\else}%
{\fi}%
}{%
\bigintcalcAdd{\bigintcalcSub{\number#3}{\number#2}}{3}%
}{ }%
}%
%%-------------------------------------------------------------------------
%% A "variable" \Amacro and the routine \setAmacro for setting it's value.
%%.........................................................................
\newcommand\Amacro{1}%
\newcommand\setAmacro[1]{\renewcommand\Amacro{#1}}%
\makeatother
\begin{document}
The \verb|<number>|-argument of \verb|\choosetext| can hold anything that
expands to the components of a quantity that is subsumable under the term
\verb|<number>| which is explained in Donald E. Knuth's The TeXbook,
Chapter 24: Summary of Vertical Mode.
\bigskip
Thus the \verb|<number>|-argument of \verb|\choosetext| can hold a sequence
of digits, e.g., the digit \verb|5|:
\bigskip
\choosetext{5}{1}{14}%
{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\bigskip
The \verb|<number>|-argument of \verb|\choosetext| can as well hold a
macro-token which serves as variable/placeholder for numerical values.
\bigskip
\setAmacro{9}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{7}{12}%
{Text in case number is smaller than 7}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is larger than 12}%
\hrulefill
\setAmacro{9}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{4}{8}%
{Text in case number is smaller than 4}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is larger than 8}%
\hrulefill
\setAmacro{17}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{1}{14}%
{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{14}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{1}{14}%
{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{13}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{1}{14}%
{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{12}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{1}{14}%
{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{11}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{1}{14}%
{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{10}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{1}{14}%
{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{9}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{1}{14}%
{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{8}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{1}{14}%
{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{7}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{1}{14}%
{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{6}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{1}{14}%
{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{5}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{1}{14}%
{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{4}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{1}{14}%
{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{3}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{1}{14}%
{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{2}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{1}{14}%
{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{1}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{1}{14}%
{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{0}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{1}{14}%
{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\hrulefill
\setAmacro{-1}%
\verb|\Amacro| expands to the number \Amacro:
\choosetext{\Amacro}{1}{14}%
{Text in case number is smaller than 1}%
{Text in case number is 1}%
{Text in case number is 2}%
{Text in case number is 3}%
{Text in case number is 4}%
{Text in case number is 5}%
{Text in case number is 6}%
{Text in case number is 7}%
{Text in case number is 8}%
{Text in case number is 9}%
{Text in case number is 10}%
{Text in case number is 11}%
{Text in case number is 12}%
{Text in case number is 13}%
{Text in case number is 14}%
{Text in case number is larger than 14}%
\end{document}
