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kotlinlang

Hello, I'm incubating client-server WEB framework. I want it to support both client and server side rendering and hydration.
So here's the problem:
• Having to define code that runs only on browser side and implements UI interactions needs to be in separate file. Not yet so annoying.
• As I have to reference JS side-code from my component in common, I need to create expect declaration for it and mark it actual. Than I need to crate dummy actual implementation for other backends(like JVM), that just throws an exception saying it suppose not be executed on server-side. This is pretty annoying.
I ended up creating dukat-like tool that generates declarations from WebIDL to expect declarations for common, actual external declarations for JS and actual dummy implementations for other backeds. It allowed me to write client-side code inside components in common.
What do you think of this solution? Any ideas for cleaner solution?