Added infrastructure for reading files

src/main.rs

@@ -19,13 +19,29 @@ mod eval;
 
 fn main() {
     let args: Vec<String> = std::env::args().collect();
-    println!("Schala v 0.02");
     if let Some(filename) = args.get(1) {
         let mut source_file = File::open(&Path::new(filename)).unwrap();
         let mut buffer = String::new();
         source_file.read_to_string(&mut buffer).unwrap();
-        panic!("Not implemented yet");
+
+        let tokens = match tokenize(&buffer) {
+            Some(t) => t,
+            None => { println!("Tokenization error"); return; }
+        };
+
+        let ast = match parse(&tokens, &[]) {
+            Ok(ast) => ast,
+            Err(err) => { println!("Parse error: {:?}", err); return; }
+        };
+
+        let mut evaluator = Evaluator::new();
+        let results = evaluator.run(ast);
+        for result in results.iter() {
+            println!("{}", result);
+        }
+
     } else {
+        println!("Schala v 0.02");
         let initial_state = InterpreterState {
             show_tokens: false,
             show_parse: false,