Clojurians Log v2

What are some approaches you guys use to interpret your parse tree?

you can use multimethods dispatching on node type

use a zipper to navigate the tree

or heck, just use https://clojure.github.io/clojure/clojure.walk-api.html

recommend using postwalk, and then writing a function to do whatever you’re thinking

depends on how you want to eval, it’s a wee bit harder for compilation, but not much. You just need to make sure you emit a string. One solution would be to treat it as a side effect of whatever function you use

admittedly, when I last did this I wasn’t using an instaparse’d parse tree, so maybe the technique varies a bit

think I re-implemented postwalk also

seems instaparse you could maybe just use insta/transform

which must do a walk of the tree, and takes a map of node type to function

@marcofiset insta/transform has always been sufficient for my use cases. Is there more sophisticated functionality you're looking for? If so, clojure.walk/[pre|post]walk might be the next step up.

I am not looking for anything particular, just wanted to start a discussion on the subject. I'm using multi methods for the moment and I was curious about what other people might be using.

I didn't know about insta/transform, I'll definitely take a look.

Yeah, instaparse.core/transform is a simple function that does the trick for simple parse tree consumption.

Hey, that rhymes

@marcofiset Take a look at this section of the readme: https://github.com/engelberg/instaparse#transforming-the-tree

Wow, I'm really impressed with the arithmetic example! Very straightforward and simple. My multi methods solution is going to the trash and will be replaced by something similar 😃