[kwertzzz]

I am wondering why the julia lox interpreter is so slow. Could it be that there is a lot of type unstable code or could it be an issue with julia's garbage collector? (I can relate to the comment that it is quite hard to find usable information from julia's profiler).

[adgjlsfhk1]

I'm pretty sure it is type instability. The faster way to do this would be with something like https://github.com/YingboMa/Unityper.jl which would fix that. The problem with profiling unstable code in Julia is that it makes everything slow so the profiler will just show a big mess of everything being slow. We do need better resources, but I have no idea what they would like like.

[lukemerrick]

I actually played with Unityper.jl and SumTypes.jl, but my conclusion was that if I was going to depart from dispatch on Julia types in my code, I might as well just stick to an untyped tree, since either way I'd have to have a single `evaluate` function for interpreting any kind of node.

Reconsidering now, it seems that there might be benefits beyond type dispatch to having a typed syntax tree, so maybe I'll give that a shot as a next step!

[nsajko]

What do you mean by "We do need better resources"?

[adgjlsfhk1]

There currently don't exist great tools to figure out why type unstable code is slow. @code_warntype and Cthulhu can help find type stability problems, but they're pretty hard to use for newer users (or big functions)