l42.tex

   1 \vbox{
   2 \begin{framed}
   3 \begin{internallinenumbers}
   4 \noindent\verb2#!2\verb!/usr/bin/perl -w!\\
   5 \verb!use strict;!\\
   6 \verb!use warnings;!\\
   7 \verb!my $text= 'Variable names in Perl can have several formats. Usually,!
   8
   9 \end{internallinenumbers}
  10 \verb!they must begin with a letter or underscore, in which case they!
  11 \verb!can be arbitrarily long (up to an internal limit of 251 characters)!
  12 \verb!and may contain letters, digits, underscores, or the special!
  13 \verb!sequence :: or \'. In this case, the part before the last :: or \'!
  14 \verb!is taken to be a package qualifier; see perlmod.';!
  15
  16 \begin{internallinenumbers}
  17 ~\\
  18 \noindent
  19 \verb!while ($text =~ /\b(\w{5,})\b/g)!\\
  20 \verb!  {!\\
  21 \verb!    print "$1\n";!\\
  22 \verb!  }!
  23 \end{internallinenumbers}
  24 \end{framed}
  25 }
  26 \label{lst:l42.pl}
  27 \resetlinenumber