Purchase

The delegate that handles purchases

<delegate name="purchase" javaClass="games.strategy.triplea.delegate.PurchaseDelegate" display="Purchase Units"/>

<step name="americanPlace" delegate="place" player="Americans"/>

Also a trigger option

<attatchment name="coolstuffhappens" attatchTo="Russians" javaClass="games.strategy.triplea.attatchments.TriggerAttachment" type="player">

   <option name="trigger" value="objectiveAttachment1"/>
   <option name="frontier" value="productionRussian"/>
   <option name="placement" value="3 Sea Zone:battleship:transport" count="2"/>
   <option name="placement" value="5 Sea Zone:battleship" count="3"/>
   <option name="purchase" value="tank:cruiser" count="2"/>
   <option name="tech" value="warBonds"/>
   <option name="invert" value="true"/>

</attatchment> trigger, any ruleAttachment, this is the conditional tested to activate whatever changes this attachment represents.

purchase adds the following units the player's purchase for the turn