Crafting a Lox Interpreter in Rust, Part 1 | Hacker News Reader

Crafting a Lox Interpreter in Rust, Part 1

diegofreijo.com

You don't have to consume the " token outside of the string function. In the scanner you could have peeked the " (and certain other things) before calling advance() or added a backwards() opposing your advance() you'd call before string() and it's ilk.

One cool pattern for tokens is a T! macro:

   macro_rules! T {
        (+) => { Token::Add },
        (-) => { Token::Sub },
        // ...
   }

This is really nice because it lets you match against tokens with `T![+]` instead of `Token::Add`.

Interested to see how you handle the nested compilers in the bytecode compiler once you hit functions. I still haven't gotten my rust-lox compiler handling this in an elegant way.

What's the issue with nested compilers in Lox?

The implementation recommended in the book involves allocating a new compiler struct for each function with a pointer to the enclosing compiler. I found this very awkward in rust. Additionally the nested compiler needs to share the lexer (which is lazy thus mutable).

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