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| <html> |
| <body> |
| |
| This package contains interfaces related to inter-definition <i>references</i>. |
| |
| <p> |
| Definitions typically refer to other definitions indirectly, by name, |
| using an <code>IReference</code>. |
| This indirection scheme allows definitions to be shared across projects. |
| This is important because there are many definitions in the core SWCs |
| that many projects use -- such as the Flash, AIR, and Flex SWCs -- and |
| it would waste memory to keep of copy of all of them in each project. |
| </p> |
| |
| <p> |
| For example, consider the <code>UIComponent</code> class |
| in <code>framework.swc</code>, which extends <code>Sprite</code>, |
| and consider two Flex projects, |
| one of which links against <code>playerglogal.swc</code> |
| and the other links against <code>airglobal.swc</code>. |
| In one project, the superclass of <code>UIComponent</code> |
| is the <code>flash.display.Sprite</code> class in |
| <code>playerglobal.swc</code>; in the other, it is the |
| <code>flash.display.Sprite</code> class in <code>airglobal.swc</code>. |
| (They could be different, even though they have the same name.) |
| Therefore, if we want to have a project-independent class definition |
| for <code>UIComponent</code>, it cannot refer directly to the definition |
| for its superclass. Instead, it stores an <code>IReference</code> to |
| <code>flash.display.Sprite</code>, which gets resolved differently |
| in the two projects. |
| </p> |
| |
| <p> |
| In some cases, is definition can keep direct references to other definitions. |
| For example, a function definition keeps direct references to the definitions |
| for its parameters, and a class definition keeps direct references to the |
| definitions for its events, styles, and effects. |
| </p> |
| |
| </body> |
| </html> |
