Devlog 12: Scoping is hard

I’ve been working on getting Ile ready to ship, and I had a small, significant feature to implement: scoping. This is basically when a function is called and uses the scope that it was a part of when it was created instead of the scope it was called in. This was hard.

To implement this, my first thought was write yet another lookup function to find the correct module’s stack and walk the function in the stack. Unfortunately, the compiler didn’t like this. I couldn’t get it done without having 2 different mutable references to the stack at the same time, so it was off the table. What I ended up going for was when a function is called, it clones (memory-efficient, amirite?!) its entire scope and walks inside it. After the function executes, it then sets the value of its module’s scope to the current value of the scope it just walked in, so as to update it with any changes. Makes sense, right? RIGHT?!

Anyway, there isn’t really a picture to show, so here’s tests passing.