Add proc(#const x: Type) to enforce a constant parameter (but not polymorphic) to a procedure

src/check_expr.cpp

@@ -5991,6 +5991,15 @@ CALL_ARGUMENT_CHECKER(check_call_arguments_internal) {
 				}
 				score += s;
 
+				if (e->flags & EntityFlag_ConstInput) {
+					if (o.mode != Addressing_Constant) {
+						if (show_error) {
+							error(o.expr, "Expected a constant value for the argument '%.*s'", LIT(e->token.string));
+						}
+						err = CallArgumentError_NoneConstantParameter;
+					}
+				}
+
 				if (o.mode == Addressing_Type && is_type_typeid(e->type)) {
 					add_type_info_type(c, o.type);
 					add_type_and_value(c->info, o.expr, Addressing_Value, e->type, exact_value_typeid(o.type));
@@ -6246,6 +6255,15 @@ CALL_ARGUMENT_CHECKER(check_named_call_arguments) {
 					}
 					err = CallArgumentError_WrongTypes;
 				}
+
+				if (e->flags & EntityFlag_ConstInput) {
+					if (o->mode != Addressing_Constant) {
+						if (show_error) {
+							error(o->expr, "Expected a constant value for the argument '%.*s'", LIT(e->token.string));
+						}
+						err = CallArgumentError_NoneConstantParameter;
+					}
+				}
 			}
 			score += s;
 		}