#!/usr/bin/perl -w
use strict;
use Data::Dumper;
my $verbose = (@ARGV && $ARGV[0] eq '-v' && shift);
if(@ARGV){
    $^I = ".orig";
}else{
    warn "$0: Reading from stdin\n" if -t STDIN;
}
my $code = "while (<>){\n";
while (<DATA>){
    chomp;
    my ($in,$out) = split /\s*=>\s*/;
    next unless $in && $out;
    $code .= "s{\\Q$in\\E}{$out}g";
    $code .= "&& printf STDERR qq($in => $out at \$ARGV line \$.\\n)" if $verbose;
    $code .= ";\n";
}
$code .= "print;\n}\n";
eval "{ $code } 1" ||die;
__END__
analysed => analyzed