Wow! I see your points TGI, thanks! About the '||' and 'or' thing this was my bad, I was aware of the difference. I think using and's and or's is pretty cool. Coming from a Java/C# background I'd say they are most expressive features. I have not been into big Perl projects yet, so I guess I have not faced the drawbacks.
Anyway, I cleaned up more code using the map{} magic and current 'version' is:
use strict;
use warnings;

my @params=qw(input output pattern replacement);
my %settings; @settings{@params}=("0")x @params;
foreach my $key (sort keys %settings) {
    print "$key="; 
    chomp($settings{$key}=<>);
    }
open IN,"<",$settings{input} or die "not a rockstar today"; 

-e $settings{output} and die("File Exists..will not override!")
    or 
open(OUT,">",$settings{output}) or die "Error while opening file: $!";

print OUT map { if(s/$settings{pattern}/$settings{replacement}/g) 
    {$_} else {$_} } (<IN>);

close (IN) and close (OUT);

[download]

As a freshman, I just can't enough of this kind of writing! :)

In reply to Re^3: Not A Rockstar File Manipulator Today by ptoulis
in thread Not A Rockstar File Manipulator Today by koolgirl

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