###############################
# try to sort fields as numbers first, then as strings
# keep going until there's a difference

sub smart_sort
{
  my @a = split /[\s_]+/, lc($a);
  my @b = split /[\s_]+/, lc($b);
  
  for my $i ( 0..(@a < @b ? $#a : $#b) )
  {
    if ( $a[$i] =~ $NUMBER_ONLY_REGEX  # line 214
     and $b[$i] =~ $NUMBER_ONLY_REGEX
     and $a[$i] <=> $b[$i] )
    {
      return $a[$i] <=> $b[$i];
    }
    elsif ( ( my @ai = /^(\d+)(.+)/ )  # error/bug is here
        and ( my @bi = /^(\d+)(.+)/ ) )
    {
      if ( $ai[0] <=> $bi[0] )
      {
        return $ai[0] <=> $bi[0];
      }
      elsif ( $ai[1] cmp $bi[1] )
      {
        return $ai[1] cmp $bi[1];
      }
    }  
    elsif( $a[$i] cmp $b[$i] )
    {
      return $a[$i] cmp $b[$i];
    }
  }
  return $a cmp $b;
}

##</code><code>##

sub smart_sort
{
  my @a = lc($a) =~ /(\d+|[a-z]+)/ig; # better split on fields
  my @b = lc($b) =~ /(\d+|[a-z]+)/ig;

  for my $i ( 0..(@a < @b ? $#a : $#b) )
  {
    # try numbers first
    if ( $a[$i] =~ $NUMBER_ONLY_REGEX 
     and $b[$i] =~ $NUMBER_ONLY_REGEX
     and $a[$i] <=> $b[$i] )
    {
      return $a[$i] <=> $b[$i];
    }
    
    # fallback to string compare
    if( $a[$i] cmp $b[$i] )        # no "elsif"
    {
      return $a[$i] cmp $b[$i];
    }
  }
  
  # can't decide by fields, decide by whole string
  return $a cmp $b;
}