refactor(tazjin/rlox): Constructor for interpreter with globals

Change-Id: Id8242c22500c8e2781cc656d3faabb28d9bdf091
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2383
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI

users/tazjin/rlox/src/main.rs

@@ -25,14 +25,14 @@ fn main() {
 // Run Lox code from a file and print results to stdout
 fn run_file(file: &str) {
     let contents = fs::read_to_string(file).expect("failed to read the input file");
-    let mut lox = interpreter::Interpreter::default();
+    let mut lox = interpreter::Interpreter::create();
     run(&mut lox, &contents);
 }
 
 // Evaluate Lox code interactively in a shitty REPL.
 fn run_prompt() {
     let mut line = String::new();
-    let mut lox = interpreter::Interpreter::default();
+    let mut lox = interpreter::Interpreter::create();
 
     loop {
         print!("> ");