Can I reference a library subsystem inside the library itself?

I have a model and an associated library for subsystems that are used in multiple places. I have Block A which I have created which addresses a general case of some opperatasion, and needs the inputs to be processed a certain way depending on the use case.

I have a certasadin use case which is overwhelmingly common which I would like to create Block B to handle. This would be the custom logic for the case, and being fed into Block A. Is this possible to accomplish in a single library file? I want them to be linked, so that Block B will also be updated if Block A is changed.

Something like:

Block A          Block B
-----------      -----------------------
|  Stuff  |      |  Stuff -> Block A   |
-----------      -----------------------

Answer 1

[Fangjun Jiang]

Yes. In the same library file, create A first, then drag and drop A to create B. Save file. Next, modify A, save file. See the A inside B changes.

[Sean Franklin]

Thank you, works as described.

It was my previous understanding that this would have just created a duplicate.