I am trying to print the files in the current directory that are not perl scripts. For this, I tried something like this: 
sub list_files{

    opendir(my $dir,".") or die "Could not open current directory";
    while (my $file = readdir($dir)) {
        print "$file\n" if ($file=~m/(?!\.pl$)/);
    }
    closedir $dir;

}

[download]
What I try here is "all files that don't match something with .pl at the end". But it still prints everything. So I have tried something like this: 
sub list_files{

    opendir(my $dir,".") or die "Could not open current directory";
    while (my $file = readdir($dir)) {
        print "$file\n" if (!($file=~m/(?=\.pl$)/));
    }
    closedir $dir;

}

[download]
The second one does what I want. Both seem to be similar however they don't behave the same. Why?

Additional question: The scripts prints also "." and "..", why are they and can it be avoid? I want to make some changes in the file names that are in the current directory. But not on "." and ".."

In reply to Regex negative lookahead by aeqr

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