Displaying Discounts

[System Administrator <agree@godzone.net.nz>]

I have been trying to solve the 'buy 3 get 1 free' discount and have
managed to get it to work ( sort of :-)

Now I want to be able to display the discount on the entire order in
the shopping cart, the receipt and order etc.  I have included below
what I have done but I am having a lot of trouble with the fact that
the various tags return currency rather than numbers and then when I
try to convert my result to currency I get '.00'.

In the item-list to display the items I have the following;
   </td><td [var TABLEFG] valign=top align=right>
      [item-subtotal]
      [calc]
         $MySubTotal += ( substr( '[item-price]', 1 ) * [item-quantity] );
         return( '' );
      [/calc]
   </td>

And at the bottom of the table I have;
[calc]
   my( $SubTotal ) = substr( '[subtotal]', 1 );
   my( $OrderDiscount ) = $MySubTotal - $SubTotal;
   if ( $OrderDiscount ) {
      return( qq{
<tr>
   <td __HEADERBG__ colspan=4 align=right valign=center>
      <font color="__HEADERTEXT__">
      <b>[L]Discount[/L]</b>
      </font>
   </td><td [var TABLEFG] align=right valign=center>
      $OrderDiscount
   </td>
</tr>} );
   } else {
      return('');
   }
[/calc]

This produces a 5 in the cell, which is the correct amount. If I use
[currency]$OrderDiscount[/currency] I get .00 instead of $5.00 which
is what I want.

Surely there must be a better way to do this.
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Glen Eustace, on behalf of
GodZone Internet Services, a division of AGRE Enterprises Limited
P.O. Box 8020, Palmerston North, New Zealand
Ph: +64 6 356 2562, Fax: +64 6 357 0271
http://www.godzone.net.nz, EMail: agree@godzone.net.nz, ICQ: 10397208
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