I am especially interested by the characterisation of handling interactions between different AST nodes. I think interactions between features are very hard to

I am especially interested by the characterisation of handling interactions between different AST nodes. I think interactions between features are very hard to think about. I think constructed languages have the opportunity to think about potential interactions that would be useful and aim to support those ones. But there's lots of permutations to features. Just look at async functions in Rust and coloured functions. It's such as pain. It also reminds me and brings up thoughts about "the expression problem" [0] How do you think which combinations of features would be useful upfront? For example: there's interactions between memory management, garbage collection, async, multithreading, coroutines, closures, the stack, FFI. It's all very complicated. [0]: https://en.wikipedia.org/wiki/Expression_problem https://en.wikipedia.org/wiki/Expression_problem