When applied to a class or a member with internal visibility allows to use it from public inline functions and makes it effectively public.

Public inline functions cannot use non-public API, since if they are inlined, those non-public API references would violate access restrictions at a call site (http://kotlinlang.org/docs/reference/inline-functions.html#public-inline-restrictions).

To overcome this restriction an internal declaration can be annotated with the @PublishedApi annotation:

  • this allows to call that declaration from public inline functions;
  • the declaration becomes effectively public, and this should be considered with respect to binary compatibility maintaining.