Generating dummy text programatically using TeX/LaTeX

Question

As part of an attempt to debug another problem, I have a need for a TeX/LaTeX command that generates some dummy text in place. I know of lipsum and blindtext, but they are not what they want. What I have in mind is a command that takes the following arguments: a string (s) and integers (k and n), and produces k occurrences of s per line (no spaces) for n lines. I think this should be possible, even if one has to drop down to TeX to do it. After all, TeX is a text processing Turing complete programming language. Unfortunately, my knowledge of TeX could fit on a postage stamp with space left over, so I'm asking on this forum.

Answer 1

The simplest way IMHO to do it is to use \foreach provided by the pgffor package. There is also the lower level \loop\ifnum\j<\k ... \repeat loop which could also be used. However, you need to wrap the inner loop in a group to mask the inner \repeat.

As Andrey already stated there are the open question about how to handle line breaks exactly. I simply use a \\ here, but you might need something else instead, dependent on the exact application. However, the principle usage of the loops is the same.

\documentclass{article}

\usepackage{pgffor}

\newcommand\dummytext[3]{%
    \foreach \n in {1,...,#3} {%
        \foreach \k in {1,...,#2} {%
            #1%
        }%
        \\
    }%
}

\begin{document}


\dummytext{HelloWorld}{5}{10}% 10 lines of 5x 'HelloWorld'

\end{document}

Answer 2

And a Plain TeX-style solution using \loop … \repeat:

\documentclass{article}

\makeatletter
\newcommand{\dummy@line}[2]{%
  \begingroup
    \@tempcnta=#2
    \loop\ifnum\@tempcnta>0
      #1\space
      \advance\@tempcnta by -1
    \repeat
  \endgroup}
\newcommand{\dummytext}[3]{%
  \begingroup
    \@tempcnta=#3
    \par\noindent
    \loop\ifnum\@tempcnta>0
      \dummy@line{#1}{#2}\\
      \advance\@tempcnta by -1
    \repeat
    \par
  \endgroup}
\makeatother

\begin{document}

\dummytext{abc}{3}{3}

\end{document}

Answer 3

You mentioned already blindtext. My first thought was, why not using it? You need only to redefine \blindtext@text to get your string. The other values are optional parameters for \Blindtext.

Unfortunately the missing spaces need also a redefiniton of \blindtext. If you allow spaces (see comments to your question), then just delete the redefiniton of \blindtext.

Below is an example.

\documentclass[11pt, a4paper,english]{article}
\usepackage{babel}
\usepackage{blindtext}
\begin{document}
\makeatletter
%Define text s
\renewcommand\blindtext@text{ab}
\renewcommand\blindtext@parstart{}%since blindtext version 2.0
%remove spaces
\renewcommand{\blindtext}[1][\value{blindtext}]{%
  \blind@checklanguage
  \blind@countxx=1 %
  \loop
    \blindtext@text%    here was a \
  \ifnum\blind@countxx<#1\advance\blind@countxx by 1 %
  \repeat
}
\makeatother

%5 lines
%7repetions
\Blindtext[5][7]

\end{document}

Answer 4

Using LaTeX3 it's almost a one liner; the \dummy_endline: macro makes sure that a paragraph is terminated after each line; of course, if the copies of the string fill more than a line, they will be wrapped. If you don't care about Underfull \hbox messages, put \linebreak in place of \dummy_endline:.

\documentclass{article}
\usepackage{xparse}
\ExplSyntaxOn
\NewDocumentCommand{\dummy}{m m m}
  {
   \prg_replicate:nn { #3 }
     {
      \prg_replicate:nn { #2 } { #1 \hfill } \dummy_endline:
     }
 }
\cs_new:Npn \dummy_endline: 
  { { \parfillskip=0pt\par } }

\ExplSyntaxOff

\begin{document}

\setlength{\parindent}{0pt}

\dummy{HelloWorld!}{5}{10}

\end{document}