Mrthfx

You can use the foreach-command from PGF/TikZ.

documentclass{minimal}

usepackage{pgffor}

newcommand{cmd}{-x-}

% to provide your syntax

newcommand{Repeat}[2]{% repeat already defined

    foreach n in {1,...,#1}{#2}

}

begin{document}

foreach n in {1,...,4}{cmd}



Repeat{6}{cmd}

end{document}

For more information see the pgfmanual.pdf, section 56, pp. 504 an following.

There’s also a TeX-Way see e.g. this page (in german …)

multido has a simple interface for replication:

documentclass{article}

usepackage{multido}

newcommand{cmd}{-x-}

newcommand{Repeat}{multido{i=1+1}}

begin{document}



Repeat{6}{cmd}

end{document}

Here some implementation I came up with which doesn't need any extra package. It uses numexpr to avoid counters and is fully expandable.

documentclass{article}



makeatletter

newcommand{Repeat}[1]{%

    expandafter@Repeatexpandafter{thenumexpr #1relax}%

}



def@Repeat#1{%

    ifnum#1>0

        expandafter@@Repeatexpandafter{thenumexpr #1-1expandafterrelaxexpandafter}%

    else

        expandafter@gobble

    fi

}

def@@Repeat#1#2{%

    @Repeat{#1}{#2}#2%

}

makeatother



begin{document}



Repeat{0}{test }



Repeat{1}{test }



Repeat{2}{test }



Repeat{3}{test }



Repeat{4}{test }



Repeat{5}{test }



edefTEST{Repeat{5}{test }}

texttt{meaningTEST}



end{document}

Plain and simple (pun intended):

deffoo{keke}

defbar#1#2{count0=#1 loop ifnumcount0>0 advancecount0 by -1 #2repeat}

bar3foo % results in kekekekekeke

bye

Token list registers expand more quickly, so if it suits you, you could also do:

newtoksfoo foo={keke}

defbar#1#2{count0=#1 loop ifnumcount0>0 advancecount0 by -1 the#2repeat}

bar3foo % results in kekekekekeke

bye

Repeating in an expendable way using e-tex additions (from http://www.tug.org/TUGboat/tb29-2/tb92jackowski.pdf):

deffoo{keke}

defgobbleone#1{}

longdefreplicate#1#2{% 

  ifnumnumexpr#1>0 

    #2expandafterreplicateexpandafter 

    {numbernumexpr#1-1expandafter}% 

  else 

    expandaftergobbleone 

  fi{#2}}

replicate3foo % results in kekekekekeke

bye

Of course, the simple answer to the OP is: use loop. But there are more codes here signed as "clever", if the loop is done only at expand processor level. And more "clever" codes here do this without using of eTeX primitives.

So, I give two codes here. You can explore them from "cleverness" point of view:).

First code uses known trick with romannumeral #1000 which expands to #1 "em"s and then we do loop over these "em"s over input stream. The main difference from the similar code presented here by @Joseph is that we needn't to read whole long sequence of "em"s again and again:

defreplicate#1{expandafterrepUexpandafter{romannumeralnumber#1000}}

defrepU#1#2{repV{#2}#1;}

defrepV#1#2{ifx#2;else#1fihererepV{#1}fi}

deffihere#1fi{fi#1}



message{replicate{27}{abc}}

bye

The second code is inspired by second code presented here by @Joseph where each decimal digit is processed individually. The code (in the accepted answer) uses nested csnames. I do the same without nested csnames and the code is more compact. Of course, it works at expand processor level without any need of eTeX primitives:

defreplicate#1{expandafterrepAnumber#1;;}

defrepA#1#2;#3;{ifx;#2;repB#1#3fi repA#2;#1#3;}

defrepB#1fi#2;#3;{firepC{#1}}

defrepC#1#2{repD{#2}#1;}

defrepD#1#2{ifx#2;else repE{#1}#2fi}

defrepE#1#2fi{fi repF#2{#1}repD{repF{10}{#1}}}

defrepF#1#2{ifcase#1 or#2or#2#2or#2#2#2or#2#2#2#2or#2#2#2#2#2or

   #2#2#2#2#2#2or#2#2#2#2#2#2#2or#2#2#2#2#2#2#2#2or

   #2#2#2#2#2#2#2#2#2or#2#2#2#2#2#2#2#2#2#2fi}



message{replicate{27}{abc}}

bye

Here is an example with loop and newcommand:

documentclass{article}

newcounter{z}

newcommandy[2]{

  loop ifnumvalue{z} < #1

    #2%

    stepcounter{z}%

  repeat

}

begin{document}

y{10}{Hello}

end{document}

I tried an alternative to the clever csname governed expansion from Joseph's answer borrowed from expl3 code.

eTeX is used only to allow input to be an expression: else replace thenumexpr at the start by number.

This is less efficient than the David Kastrup + LaTeX team code, although perhaps it becomes about the same when the number of replications is in the thousands (not much tested).

The initial version of this answer had more complicated code which was at about the same level of efficiency. There was an unfortunate chardefz@=0 in that code, which is very wrong and I don't know why it was there.

This answer handles more efficiently than Joseph's the case of a negative asked for number of replication.

It could be easily reworked into a macro (working only in a edef) leaving tokens behind it rather than in front of it while expanding.

catcode`@ 11



defJFsignfork #10-#2#3krof {#2}

%chardefz@ 0 % NO! z@ is a dimen in TeX/LaTeX



defJFrep   #1{romannumeralexpandafterJFrep@athenumexpr #1;3456789XY!}%

defJFrep@a #1{JFsignfork

                  #1-JFrep@nil

                  0#1JFrep@neg

                   0-JFrep@b

              krof #1%

             }%

longdefJFrep@nil #1!#2{z@}

longdefJFrep@neg #1!#2{z@NegativeReplication}



% TeX numbers have at most 10 digits

defJFrep@b #1#2#3#4#5#6#7#8#9{JFrep@c {.#9.#8.#7.#6.#5.#4.#3.#2;#1}}

defJFrep@c #1#2#3#4!{JFrep@d .#3.#2#1!}

defJFrep@d #1;#2#3{csname JFrep@f#2#3endcsname}

longexpandafterdefcsname JFrep@f.0endcsname #1#2#3!#4%

     {csname JFrep@f#1#2endcsname#3!{#4#4#4#4#4#4#4#4#4#4}}%

longexpandafterdefcsname JFrep@f.1endcsname #1#2#3!#4%

     {csname JFrep@f#1#2endcsname#3!{#4#4#4#4#4#4#4#4#4#4}#4}%

longexpandafterdefcsname JFrep@f.2endcsname #1#2#3!#4%

     {csname JFrep@f#1#2endcsname#3!{#4#4#4#4#4#4#4#4#4#4}#4#4}%

longexpandafterdefcsname JFrep@f.3endcsname #1#2#3!#4%

     {csname JFrep@f#1#2endcsname#3!{#4#4#4#4#4#4#4#4#4#4}#4#4#4}%

longexpandafterdefcsname JFrep@f.4endcsname #1#2#3!#4%

     {csname JFrep@f#1#2endcsname#3!{#4#4#4#4#4#4#4#4#4#4}#4#4#4#4}%

longexpandafterdefcsname JFrep@f.5endcsname #1#2#3!#4%

     {csname JFrep@f#1#2endcsname#3!{#4#4#4#4#4#4#4#4#4#4}#4#4#4#4#4}%

longexpandafterdefcsname JFrep@f.6endcsname #1#2#3!#4%

     {csname JFrep@f#1#2endcsname#3!{#4#4#4#4#4#4#4#4#4#4}#4#4#4#4#4#4}%

longexpandafterdefcsname JFrep@f.7endcsname #1#2#3!#4%

     {csname JFrep@f#1#2endcsname#3!{#4#4#4#4#4#4#4#4#4#4}#4#4#4#4#4#4#4}%

longexpandafterdefcsname JFrep@f.8endcsname #1#2#3!#4%

     {csname JFrep@f#1#2endcsname#3!{#4#4#4#4#4#4#4#4#4#4}#4#4#4#4#4#4#4#4}%

longexpandafterdefcsname JFrep@f.9endcsname #1#2#3!#4%

     {csname JFrep@f#1#2endcsname#3!{#4#4#4#4#4#4#4#4#4#4}#4#4#4#4#4#4#4#4#4}%

longexpandafterdefcsname JFrep@f;1endcsname!#1{z@#1}%

longexpandafterdefcsname JFrep@f;2endcsname!#1{z@#1#1}%

longexpandafterdefcsname JFrep@f;3endcsname!#1{z@#1#1#1}%

longexpandafterdefcsname JFrep@f;4endcsname!#1{z@#1#1#1#1}%

longexpandafterdefcsname JFrep@f;5endcsname!#1{z@#1#1#1#1#1}%

longexpandafterdefcsname JFrep@f;6endcsname!#1{z@#1#1#1#1#1#1}%

longexpandafterdefcsname JFrep@f;7endcsname!#1{z@#1#1#1#1#1#1#1}%

longexpandafterdefcsname JFrep@f;8endcsname!#1{z@#1#1#1#1#1#1#1#1}%

longexpandafterdefcsname JFrep@f;9endcsname!#1{z@#1#1#1#1#1#1#1#1#1}%



catcode`@ 12



edeftest{JFrep{123}{abc}}

showtest



bye