First attempt at Java side automatic downcast feature #548
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Hi,
this is my first sketch for a Java side automatic downcast feature.
To use it do as follow:
The base type of the class hierarchy is annotated with
@Downcast
and the name of the downcast function in the target class.For example:
And the downcast function is injected into the target as follows:
Since in the case of multi toolkit library it usefull to inject some code to all toolkits (for example to register the downcastable classe) I also added:
How it works:
Any function (say foo) that returns a type that is tagged with
@Downcast
is renamed and tagged with '_ _' (for examplefoo_ _
). In addition a new pure Java function with the original name and same signature is created . This new function calls the renamed function and passes the returned value to the downcast function and returns the value returned from the downcast function. The renamed function is also annotated with@Renamed
For example: