use strict;
use warnings;

### -------------------------- Util -----------------------
sub Iterator (&)     { return $_[0] }
sub NEXTVAL         { $_[0]->() }

### -------------------------- Iterator -------------------
sub interesting_files {
    my $is_interesting = shift;
      my @queue = @_;
      return Iterator {
       while (@queue) {
             my $file = shift @queue;
             if (-d $file) { 
                 opendir my $dh, $file or next;
                 my @newfiles = grep {$_ ne "." && $_ ne ".."} readdir
+ $dh;
                 push @queue, map "$file/$_", @newfiles;
             }
             return $file if $is_interesting->($file);
       } 
       return;
      };
}

### -------------------------- FileMask -------------------
sub is_WrappedXml {
    my $file = shift;
    return 1 if $file =~ /WrappedXml.{0,5}\.xml/i;
    return;
}

### -------------------------- MAIN -----------------------
my $WrappedXml_file = interesting_files(\&is_WrappedXml, '.');
while (defined(my $file = NEXTVAL($WrappedXml_file))) {
    print "$file\n";
}
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