all field operators working with constraints

simple.program

@@ -1,2 +1,2 @@
-x = a
-return x
+x = 5 + a
+return x ** 2 * 2

src/aleo_program/constraints.rs

@@ -340,7 +340,7 @@ impl ResolvedProgram {
                             // The type of the unassigned variable depends on what is passed in
                             if std::env::args()
                                 .nth(1)
-                                .unwrap_or("true".into())
+                                .expect("variable declaration not passed in")
                                 .parse::<bool>()
                                 .is_ok()
                             {

src/language.pest

@@ -39,7 +39,7 @@ operation_binary = _ {
     operation_and | operation_or |
     operation_eq | operation_neq |
     operation_geq | operation_gt | operation_leq | operation_lt |
-    operation_add | operation_sub | operation_mul | operation_div | operation_pow
+    operation_add | operation_sub | operation_pow | operation_mul | operation_div
 }
 
 // operation_add_assign = { "+=" }