Start implementing parser

- Implemented AST + parsing for maths expressions

plang2/src/main.rs

@@ -4,14 +4,7 @@ use plang2_lib::*;
 fn main() {
 
     let code = r#"
-        // This is the main function
-        fn main() {
-            let a = 5465;
-            let b = 8;
-            let c = a + b;
-
-            print_int(c);
-        }
+        -( -5 + 2 ) * -( 2 * -5 ) + -( 2 - 6 )
     "#;
 
     let mut lexer = Lexer::new(code);
@@ -20,4 +13,9 @@ fn main() {
 
     println!("Tokens: \n{}\n", tokens);
 
+    let mut parser = Parser::new(tokens);
+    let expr = parser.parse().unwrap();
+
+    println!("{:#?}", expr);
+
 }