use File::DosGlob;
$dir=  '/home/javascript/*'; # note trailing * !!!
my @m = File::DosGlob::doglob(1,$dir);
for (@m) {
  push @m, File::DosGlob::doglob(1,$_.'/*') if -d($_);
  next unless (/\.js$/);
# put your code here to
# open file ($_) and search
  open(JS,"<$_") or die "Can't Open $_: $!";
# etc.
}