Started using unique_ptr

Nodes and variables now contain unique references to Values

src/operations/node.cpp

@@ -215,7 +215,7 @@ Value* eval_expression(Node* node, Environment* env) {
         return 0;
       }
       // Change to return copy of value [TODO]
-      return new Value(*get_value(var));
+      return get_value(var);
       break;
     //----------
     case VALUE: 
@@ -256,6 +256,7 @@ void eval_statement(Node* node, Environment* env) {
       tempVal = eval_expression(node->children[0], env);
       if (tempVal->type == BOOLEAN) {
         tempLong = get_long(tempVal);
+        delete tempVal;
         if (tempLong.size() > 1) { std::cerr << "Cannot have a vector of booleans for your if expression" << std::endl; break;}
         if (tempLong[0]) {
           eval_statement(node->children[1], env);
@@ -272,11 +273,13 @@ void eval_statement(Node* node, Environment* env) {
       tempVal = eval_expression(node->children[0], env);
       if (tempVal->type == BOOLEAN) {
         tempLong = get_long(tempVal);
+        delete tempVal;
         if (tempLong.size() > 1) { std::cerr << "Cannot have a vector of booleans for your while expression" << std::endl; break;}
         while (tempLong[0]) {
           eval_statement(node->children[1], env);
           tempVal = eval_expression(node->children[0], env);
           tempLong = get_long(tempVal);
+          delete tempVal;
           if (tempLong.size() > 1) { std::cerr << "Cannot have a vector of booleans for your while expression" << std::endl; break;}
         }
       } else {
@@ -289,6 +292,7 @@ void eval_statement(Node* node, Environment* env) {
       check_num_nodes(node, 1, "can only print out one expression at a time.");
       tempVal = eval_expression(node->children[0], env);
       std::cout << tempVal << std::endl;
+      delete tempVal;
       break;
     //------------
     case STATEMENT: // Can have a maximum of two children statement nodes
@@ -302,6 +306,8 @@ void eval_statement(Node* node, Environment* env) {
     //------------
     default:
       printf("Error, %d not a valid statement type.\n", node->type);
-      return;
+
   }
+
+  return;
 }

src/operations/node.hpp

@@ -4,6 +4,7 @@
 #include <string>
 #include <array>
 #include <iostream>
+#include <memory>
 #include "../variables/value.hpp"
 #include "../variables/environment.hpp"
 
@@ -16,7 +17,7 @@ class Environment;
 class Node {
   public:
   int type;
-  Value* value;
+  std::unique_ptr<Value> value;
 
   /* the id of the node (used for identifiers only) */
   std::string id;
@@ -29,17 +30,13 @@ class Node {
 
   std::string toString(void) const;
 
-  Node(int t, Value* v, std::string s) {
+  Node(int t, std::unique_ptr<Value> v, std::string s) : value(std::move(v)) {
     type = t;
-    value = v;
     id = s;
     num_children = 0;
-    for (uint i = 0; i < MAX_CHILDREN; i++) {
-      children[i] = nullptr;
-    }
+    std::fill(children.begin(), children.end(), nullptr);
   }
   ~Node() {
-    // delete value;
     for (uint i = 0; i < num_children; i++) {
       delete children[i];
     }
@@ -47,7 +44,6 @@ class Node {
 };
 
 // Abstract Syntax Tree Functions
-// struct Node* make_node(int type, struct Value* value, std::string id);
 void attach_node(Node* parent, Node* child);
 std::string tree_string(const Node* node, uint tabs);
 

src/operations/operators.cpp

@@ -49,6 +49,9 @@ Value* add(Value* x, Value* y) {
     ans = make_double(doubleResult);
   }
 
+  delete x;
+  delete y;
+
   return ans;
 }
 
@@ -92,6 +95,9 @@ Value* subtract(Value* x, Value* y) {
     ans = make_double(doubleResult);
   }
 
+  delete x;
+  delete y;
+
   return ans;
 }
 
@@ -135,6 +141,9 @@ Value* division(Value* x, Value* y) {
     ans = make_double(doubleResult);
   }
 
+  delete x;
+  delete y;
+
   return ans;
 }
 
@@ -178,6 +187,9 @@ Value* multiplication(Value* x, Value* y) {
     ans = make_double(doubleResult);
   }
 
+  delete x;
+  delete y;
+
   return ans;
 }
 
@@ -224,6 +236,9 @@ Value* less(Value* x, Value* y) {
     ans = make_booleans(longResult);
   }
 
+  delete x;
+  delete y;
+
   return ans;
 }
 
@@ -270,6 +285,9 @@ Value* greater(Value* x, Value* y) {
     ans = make_booleans(longResult);
   }
 
+  delete x;
+  delete y;
+
   return ans;
 }
 
@@ -316,6 +334,9 @@ Value* less_equal(Value* x, Value* y) {
     ans = make_booleans(longResult);
   }
 
+  delete x;
+  delete y;
+
   return ans;
 }
 
@@ -362,6 +383,9 @@ Value* greater_equal(Value* x, Value* y) {
     ans = make_booleans(longResult);
   }
 
+  delete x;
+  delete y;
+
   return ans;
 }
 
@@ -407,6 +431,9 @@ Value* equals(Value* x, Value* y) {
     ans = make_booleans(longResult);
   }
 
+  delete x;
+  delete y;
+
   return ans;
 }
 
@@ -452,6 +479,9 @@ Value* not_equals(Value* x, Value* y) {
     ans = make_booleans(longResult);
   }
 
+  delete x;
+  delete y;
+
   return ans;
 }
 
@@ -465,6 +495,9 @@ Value* and_value(Value* x, Value* y) {
   std::transform(x_long.begin(), x_long.end(), y_long.begin(),
                   std::back_inserter(longResult), std::logical_and<>());
 
+  delete x;
+  delete y;
+
   return make_booleans(longResult);
 }
 
@@ -478,6 +511,9 @@ Value* or_value(Value* x, Value* y) {
   std::transform(x_long.begin(), x_long.end(), y_long.begin(),
                   std::back_inserter(longResult), std::logical_or<>());
 
+  delete x;
+  delete y;
+
   return make_booleans(longResult);
 }
 
@@ -489,5 +525,7 @@ Value* not_value(Value* x) {
   std::vector<long> x_long = get_long(x);
   std::transform(x_long.begin(), x_long.end(), std::back_inserter(longResult), std::logical_not<>());
 
+  delete x;
+
   return make_booleans(longResult);
 }

src/parser/lexer.l

@@ -46,12 +46,12 @@ DIGIT [0-9]
 "input"                 {return INPUT;}
 "lambda"                {return LAMBDATAG;}
 ":"                     {return COLON;}
-"true"                  {yylval.value = new Node(VALUE, make_true(), ""); return VALUE;}
-"false"                 {yylval.value = new Node(VALUE, make_false(), ""); return VALUE;}
-\".*\"                   {yylval.value = new Node(VALUE, make_string(substring(yytext, 1, strlen(yytext) - 1)), ""); return VALUE; }
-{DIGIT}                 {std::vector<long> nums; nums.push_back(atoi(yytext)); yylval.value = new Node(VALUE, make_long(nums), ""); return VALUE;}
-{DIGIT}*"."?{DIGIT}+    {std::vector<double> decs; decs.push_back(atof(yytext)); yylval.value = new Node(VALUE, make_double(decs), ""); return VALUE;}
-[_a-zA-Z][_a-zA-Z0-9]*  {yylval.value = new Node(IDENTIFIER,  nullptr, strdup(yytext)); return IDENTIFIER;}
+"true"                  {yylval.value = new Node(VALUE, std::unique_ptr<Value>(make_true()), ""); return VALUE;}
+"false"                 {yylval.value = new Node(VALUE, std::unique_ptr<Value>(make_false()), ""); return VALUE;}
+\".*\"                   {yylval.value = new Node(VALUE, std::unique_ptr<Value>(make_string(substring(yytext, 1, strlen(yytext) - 1))), ""); return VALUE; }
+{DIGIT}                 {std::vector<long> nums; nums.push_back(atoi(yytext)); yylval.value = new Node(VALUE, std::unique_ptr<Value>(make_long(nums)), ""); return VALUE;}
+{DIGIT}*"."?{DIGIT}+    {std::vector<double> decs; decs.push_back(atof(yytext)); yylval.value = new Node(VALUE, std::unique_ptr<Value>(make_double(decs)), ""); return VALUE;}
+[_a-zA-Z][_a-zA-Z0-9]*  {yylval.value = new Node(IDENTIFIER, std::unique_ptr<Value>(nullptr), yytext); return IDENTIFIER;}
 [\n]                    {linenum++;} 
 [ \t\r]+                {}
 .                       {printf("Error: invlaid lexeme '%s'.\n", yytext); return 0;}

src/variables/environment.cpp

@@ -21,7 +21,7 @@ void add_variable(Environment* env, Variable* var) {
   // If variable exists, replace it
   Variable* temp_var = find_variable(env, var->id);
   if (temp_var != nullptr) {
-    temp_var->value = var->value;
+    temp_var->value = std::unique_ptr<Value>(new Value(*var->value));
     free(var);
     return;
   }

src/variables/variable.cpp

@@ -2,12 +2,7 @@
 #include <string>
 #include "variable.hpp"
 
-void set_value(Variable* var, Value* value) {
-  if (!var) { std::cerr << "Error: Invalid Variable" << std::endl; return; }
-  var->value = value;
-}
-
 Value* get_value(const Variable* var) {
   if (!var) { std::cerr << "Error: Invalid Variable" << std::endl; return 0; }
-  return var->value;
+  return new Value(*var->value);
 }

src/variables/variable.hpp

@@ -2,6 +2,7 @@
 #define VARIABLE_H
 
 #include <string>
+#include <memory>
 #include "../variables/value.hpp"
 
 class Value;
@@ -10,19 +11,17 @@ class Node;
 class Variable {
   public:
   std::string id;
-  Value* value;
+  std::unique_ptr<Value> value;
 
-  Variable(std::string s, Value* val) {
+  Variable(std::string s, Value* val) : value(std::move(val)) {
     id = s;
-    value = val;
   }
   ~Variable() {
-    delete value;
+
   }
 };
 
 // Variable Functions
-void set_value(Variable* var, Value* value);
 Value* get_value(const Variable* var);
 
 #endif