Initial commit for recording parse state in ast

tests/grammar.c

@@ -52,7 +52,7 @@ void test_grammar(void) {
   mpc_ast_delete(t0);
   mpc_ast_delete(t1);
   mpc_ast_delete(t2);
-
+  
   mpc_cleanup(4, Expr, Prod, Value, Maths);
   
 }