Registers type
as extension for the extension point with name extension_point_name
.
If type
has already been registered as an extension for this extension point, the existing
IOExtension object is returned.
extension_point_name |
the name of the extension point |
type |
the Type to register as extension |
extension_name |
the name for the extension |
priority |
the priority for the extension |
a IOExtension object for Type |