interpreter in rust

rust/rox/src/lib.rs

@@ -11,6 +11,7 @@ use tracing::{error, info};
 
 pub mod cli;
 pub mod expression;
+pub mod interpreter;
 pub mod keywords;
 pub mod parser;
 pub mod scanner;
@@ -30,11 +31,7 @@ pub mod tokenizer {
 /// Read the source code in a file and scan it to tokens.
 pub fn compile(source: &Path) -> Result<(), io::Error> {
     let input = fs::read_to_string(source)?;
-    let tokens = scanner::tokenize(&input);
-    match parser::generate_ast(tokens) {
-        Ok(ast) => info!("{ast:?}"),
-        Err(e) => error!("{e}"),
-    }
+    run(&input);
 
     Ok(())
 }
@@ -51,10 +48,18 @@ pub fn repl() {
             Err(e) => error!("{}", e),
         }
         let input = input.trim().to_string();
-        let tokens = scanner::tokenize(&input);
-        match parser::generate_ast(tokens) {
-            Ok(ast) => info!("{ast:?}"),
-            Err(e) => error!("{e}"),
-        }
+        run(&input);
+    }
+}
+
+/// Evaluate a Lox input string and print errors or output.
+fn run(input: &str) {
+    let tokens = scanner::tokenize(input);
+    match parser::generate_ast(tokens) {
+        Ok(ast) => match interpreter::evaluate(ast) {
+            Ok(value) => info!("{value:?}"),
+            Err(e) => error!("{e}"),
+        },
+        Err(e) => error!("{e}"),
     }
 }