disable inheritance from int bool str

assignments/PA4/bad_inherit.cl

@@ -27,6 +27,14 @@ class Ok2_2 inherits Ok1 {};
 class Ok3 inherits Ok2_1 {};
 class Ok4 inherits Ok2_2 {};
 
+(* Cool has restrictions on inheriting from basic classes *)
+
+class Err1 inherits Int {};
+class Err3 inherits String {};
+class Err3 inherits Bool {};
+class Err4 inherits Err3 {};
+class Err4 inherits NOEXIST {};
+
 
 class Main inherits IO {
     main(): Object {

assignments/PA4/mysemant

@@ -1,2 +1,2 @@
-#!/bin/csh -f
+#!/bin/bash
 ./lexer $* | ./parser $* | ./semant $* 

assignments/PA4/semant.cc

@@ -5,6 +5,7 @@
 #include <stdio.h>
 #include <stdarg.h>
 #include <utility>
+#include <vector>
 #include "cool-tree.h"
 #include "semant.h"
 #include "utilities.h"
@@ -88,25 +89,37 @@ static void initialize_constants(void)
 
 ClassTable::ClassTable(Classes classes) : semant_errors(0) , error_stream(cerr) {
     install_basic_classes();
+    std::vector<class__class* > class_vec;
     for (auto i = classes->first(); classes->more(i); i = classes->next(i)) {
         auto class_i = static_cast<class__class*>(classes->nth(i));
         if (name_to_node.find(class_i->get_name()) != name_to_node.end()) {
-            semant_error(class_i) << "Class `" << class_i->get_name() << "` was previously defined.\n";
+            semant_error(class_i) << "Class " << class_i->get_name() << " was previously defined.\n";
         }
         else {
             name_to_node[class_i->get_name()] = new ClassGraphNode(class_i, nullptr);
             // null means we have this class, but not yet build inheritence graph for it
+            class_vec.push_back(class_i);
         }
     }
-    for (auto i = classes->first(); classes->more(i); i = classes->next(i)) {
+
-        auto class_i = static_cast<class__class*>(classes->nth(i));
+    auto sym_Bool = idtable.lookup_string("Bool");
-        if (name_to_node.find(class_i->get_parent()) == name_to_node.end()) {
+    auto sym_Int = idtable.lookup_string("Int");
+    auto sym_String = idtable.lookup_string("String");
+    
+    for (auto class_i : class_vec) {
+        auto sym_parent = class_i->get_parent();
+        // Cool has restrictions on inheriting from the basic classes
+        if ( sym_parent == sym_Bool || sym_parent == sym_Int || sym_parent == sym_String) {
+            semant_error(class_i) <<  "Class " << class_i->get_name()
+                << " cannot inherit class " << sym_parent << ".\n";
+        }
+        else if (name_to_node.find(sym_parent) == name_to_node.end()) {
             semant_error(class_i) << "Class `" << class_i->get_name() << "` inherits from an undefined class `"
-                << class_i->get_parent() << "`\n";
+                << sym_parent << "`\n";
         }
         else {
-            auto class_parent = name_to_node[class_i->get_parent()];
+            auto class_parent = name_to_node[sym_parent];
-            assert(class_parent != nullptr);
+            // assert(class_parent != nullptr);
             class_parent->append_child(name_to_node[class_i->get_name()]);
         }
     }