sub pp_lcfirst(;$) {
   local $_ = @_ ? $_[0] : $_;
   s/(.)/\l$1/;
   return $_;
}

sub pp_uc(;$) {
   local $_ = @_ ? $_[0] : $_;
   s/(.*)/\U$1/;
   return $_;
}

sub pp_reverse {
   if (wantarray) {
      my @rv;
      push(@rv, pop(@_)) while @_;
      return @rv;
   } else {
      my $str = join('', @_);
      my $rv = '';
      my $i = length($str);
      $rv .= substr($str, $i, 1) while $i--;
      return $rv;
   }
}

sub spaces_to_und(;$) {
   local $_ = @_ ? $_[0] : $_;
   s/\s+/_/g;
   return $_;
}