Split arguments into a Vec

src/main.rs

@@ -140,7 +140,11 @@ impl Program {
         builder
     }
 
-    fn run_external(&mut self, filename: String) {
+    fn run_external(&mut self, arguments: String) {
+        let argument_vec: Vec<&str> = arguments.split("-").collect();
+        println!("{}", argument_vec.len());
+        let filename = argument_vec[0];
+
         // Read contents of the provided file and construct a symbolic Program from it
         let contents = fs::read_to_string(filename).expect("Something went wrong reading the file");
         let mut prog = Program::from_string(contents);