you are not in context of your

Third

instance, so no

I posted an example code, may you could take a lock

The

fun First.print()

is an extension function defined in a class/interface and therefore it has two receivers. One must be an implicit instance-receiver (of type

Second

), the second one must be the explicit receiver that is extended (of type

First

). The only way to call a function with multiple receivers is to be ‘in the context of the instance-receiver’ and then provide the second one. Where you call it (

Third().print()

), you only provide one receiver, the explicit extended receiver, and you are not in the context of any (implicit) instance-receiver. Inside the lambda of the

with

function, you have both receivers (and they are the same instance of course). I do agree, though, that either both statements should compile or none of them. Because in the

with

lambda, you don’t provide an explicit receiver either (the implicit

this

is used). Interesting… 🙂

@streetsofboston have you some solution in mind for avoid to duplicate many functions? Basically I have to create shadow functions like

fun Third.print() = print()

🤯

Not really... You could make it a regular method, not an extension function, and add a parameter to it:

fun print(receiver: First) = ...

That won't make any sense in my use case 😋