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kotlinlang

Hi! I’ve been following a tutorial on how to create a mini compiler, but the tutorial is in JavaScript. I’m trying to convert it to Kotlin, and I’ve ran into the following problem (detailed in the thread) and I’m not sure how to solve it.

traverse_js.js

What’s the Kotlin equivalent of this anonymous JS object? I’m asking about the `NumberLiteral` and `CallExpression`, they are functions, one only has `node` as parameter and the other one as both `node` and `parent`. Would this be a sealed class? Or just a class with these two functions?

You could create an interface with these 2 functions, and make `traverse` accept that interface as second argument. Then you can either create a class implementing that interface, or create an anonymous implementation of the interface on the spot, with the syntax `object : TheInterface { ... }` where you can define the functions in the `...` part

Another option is to make `traverse` accept 2 function arguments instead of that one object. And then you can pass lambdas for those. But I'd rather go the typed way

Ohhh yeah, that makes sense! The first approach seems a bit easier, I’ll try implementing that. Thank you Joffrey!