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IAnnotationReplace - use constant in annotation

Let’s highlight one new feature on release 0.21.0.

IAnnotationReplace

Utility interface that allows you to replace expressions in annotation with their values. It’s especially handy for keeping injection names in classes with constants.

Build macro attached to IAnnotationReplace will cause following change:

@Inject(MyConstants.NAME_ONE)
public var injectedOne:String;

becomes

@Inject("one")
public var injectedOne:String;

Expressions that are already constants will remain untouched so @Inject("one") will stay the same. That also applies to combinations of expressions so @Inject(MyConstants.NAME_ONE, "two") changes to @Inject("one", "two")

Currently supported values of expressions:

  • String
  • Bool
  • Int

Currently supported expressions that will be replaced:

  • Constant in current class
    • @Meta(TEST)
  • Constant in different class
    • @Meta(MyClass.TEST)
  • Constant in different class (with reference using FQCN)
    • @Meta(my.pack.MyClass.TEST)

Note that the only expressions that are replaced are [public] static var. Non-static variables are not being searched so they won’t be found.

Important: If used with IInjectorContainer the order matters:

Only this order of implementation will work because of the macro execution order - fix will come soon:

class MyClass implements IInjectorContainer implements IAnnotationReplace

To go further