Hello,

2 questions on below example from Perl cookbook,

1)Never seen while being used inside of qutation while being assign to $code(on line 11) In this case, what is $code in line 17?

2)do not understand this line s{\\Q$in\\E}{$out}g at line 17
I looked up \Q and see that it means Quote metacharacters till \E
What does "quoting metacharacters" mean? I understand what metacharacter is(special character such as $ or ^) but just what is quoting metachracter mean??

\Q -- Quote (de-meta) metacharacters till \E. 
 1 #!/usr/bin/perl -w
      2 # fixstyle - switch first set of <DATA> strings to second set
      3 #   usage: $0 [-v] [files ...]
      4 use strict;
      5 my $verbose = (@ARGV && $ARGV[0] eq '-v' && shift);
      6 if (@ARGV) {
      7   $^I = ".orig";          # preserve old files
      8 } else {
      9   die warn "$0: Reading from stdin\n" if -t STDIN;
     10 }
     11 my $code = "while (<>) {\n";
     12 # read in config, build up code to eval
     13 while (<DATA>) {
     14   chomp;
     15   my ($in, $out) = split /\s*=>\s*/;
     16   next unless $in && $out;
     17   $code .= "s{\\Q$in\\E}{$out}g";
     18   $code .= "&& printf STDERR qq($in => $out at \$ARGV line \$.
+\\n)"
     19                                                       if $verb
+ose;
     20   $code .= ";\n";
     21 }
     22 $code .= "print;\n}\n";
     23 eval "{ $code } 1" || die;
     24 __END__
     25 analysed        => analyzed
     26 built-in        => builtin
     27 chastized       => chastised
     28 commandline     => command-line
     29 de-allocate     => deallocate
     30 dropin          => drop-in
     31 hardcode        => hard-code
     32 meta-data       => metadata
     33 multicharacter  => multi-character
     34 multiway        => multi-way
     35 non-empty       => nonempty
     36 non-profit      => nonprofit
     37 non-trappable   => nontrappable
     38 pre-define      => predefine
     39 preextend       => pre-extend
     40 re-compiling    => recompiling
     41 reenter         => re-enter
     42 turnkey         => turn-key

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In reply to script fixstyle from cookbook by convenientstore

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