diff --git a/src/include/memory.h b/src/include/memory.h
index 7ed3d6f..0de55cf 100644
--- a/src/include/memory.h
+++ b/src/include/memory.h
@@ -5,14 +5,23 @@
 #include "types.h"
 using namespace std;
 
-Memory new_memory(void);
+class Memory {
+    public:
+        bool contains(string identifier);
+        bool contains_top(string identifier);
+        void add_scope(void);
+        void remove_scope(void);
 
-bool memory_contains(Memory& memory, string identifier);
+        EvalResult get(string identifier);
+        void declare(string identifier, EvalResult value);
+        void update(string identifier, EvalResult value);
 
-EvalResult memory_get(Memory& memory, string identifier);
+        Scope& _debug_top(void);
 
-void memory_set(Memory& memory, string identifier, EvalResult value);
+        Memory(void);
 
-void memory_update(Memory& memory, string identifier, EvalResult value);
+    private:
+        list<Scope> scopes;
+};
 
 #endif
\ No newline at end of file
diff --git a/src/include/types.h b/src/include/types.h
index f16947c..c1dba6a 100644
--- a/src/include/types.h
+++ b/src/include/types.h
@@ -138,9 +138,6 @@ using EvalResult = variant<monostate, int, double>;
 struct Scope {
     unordered_map<string, EvalResult> vars;
     int depth;
-    string name;
 };
 
-using Memory = list<Scope>;
-
 #endif
\ No newline at end of file
diff --git a/src/interpreter.cpp b/src/interpreter.cpp
index 6e4bb96..b12b561 100644
--- a/src/interpreter.cpp
+++ b/src/interpreter.cpp
@@ -39,7 +39,10 @@ EvalResult eval(Node &ast, Memory &memory) {
                 return {};
             } break;
             case NodeType::Bloc: {
-
+                memory.add_scope();
+                eval(node.children[0], memory);
+                memory.remove_scope();
+                return {};
             } break;
             case NodeType::Plus: {
                 int e1 = get<int>(eval(node.children[0], memory));
@@ -81,7 +84,9 @@ EvalResult eval(Node &ast, Memory &memory) {
                 Token identifierTok = get<Token>(node.children[1]);
                 string identifier = get<string>(identifierTok.data);
 
-                memory_set(memory, identifier, { });
+                if (memory.contains_top(identifier)) throw RuntimeError("Identifier \""+identifier+"\" was already declared in this scope", identifierTok.pos);
+
+                memory.declare(identifier, { });
                 
                 return {};
             } break;
@@ -92,7 +97,9 @@ EvalResult eval(Node &ast, Memory &memory) {
                 string identifier = get<string>(identifierTok.data);
                 EvalResult value = eval(node.children[2], memory);
 
-                memory_set(memory, identifier, value);
+                if (memory.contains_top(identifier)) throw RuntimeError("Identifier \""+identifier+"\" was already declared in this scope", identifierTok.pos);
+
+                memory.declare(identifier, value);
 
                 return value;
             } break;
@@ -101,9 +108,9 @@ EvalResult eval(Node &ast, Memory &memory) {
                 string identifier = get<string>(identifierTok.data);
                 EvalResult value = eval(node.children[1], memory);
 
-                if (!memory_contains(memory, identifier)) throw RuntimeError("Unknown identifier \""+identifier+"\"", identifierTok.pos);
+                if (!memory.contains(identifier)) throw RuntimeError("Unknown identifier \""+identifier+"\"", identifierTok.pos);
 
-                memory_update(memory, identifier, value);
+                memory.update(identifier, value);
 
                 return value;
             } break;
@@ -111,13 +118,13 @@ EvalResult eval(Node &ast, Memory &memory) {
                 Token identifierTok = get<Token>(node.children[0]);
                 string identifier = get<string>(identifierTok.data);
 
-                if (!memory_contains(memory, identifier)) throw RuntimeError("Unknown identifier \""+identifier+"\"", identifierTok.pos);
+                if (!memory.contains(identifier)) throw RuntimeError("Unknown identifier \""+identifier+"\"", identifierTok.pos);
 
-                EvalResult value = memory_get(memory, identifier);
+                EvalResult value = memory.get(identifier);
 
                 if (holds_alternative<int>(value)) {
-                    memory_update(memory, identifier, get<int>(value) + 1);
-                    return memory_get(memory, identifier);
+                    memory.update(identifier, get<int>(value) + 1);
+                    return memory.get(identifier);
                 }
                 else if (holds_alternative<monostate>(value)) {
                     throw RuntimeError("Accessing uninitialized identifier \""+identifier+"\"", identifierTok.pos);
@@ -129,12 +136,12 @@ EvalResult eval(Node &ast, Memory &memory) {
                 Token identifierTok = get<Token>(node.children[0]);
                 string identifier = get<string>(identifierTok.data);
 
-                if (!memory_contains(memory, identifier)) throw RuntimeError("Unknown identifier \""+identifier+"\"", identifierTok.pos);
+                if (!memory.contains(identifier)) throw RuntimeError("Unknown identifier \""+identifier+"\"", identifierTok.pos);
 
-                EvalResult value = memory_get(memory, identifier);
+                EvalResult value = memory.get(identifier);
 
-                if (holds_alternative<int>(memory_get(memory, identifier))) {
-                    memory_update(memory, identifier, get<int>(value) + 1);
+                if (holds_alternative<int>(memory.get(identifier))) {
+                    memory.update(identifier, get<int>(value) + 1);
                 }
                 else if (holds_alternative<monostate>(value)) {
                     throw RuntimeError("Accessing uninitialized identifier \""+identifier+"\"", identifierTok.pos);
@@ -146,13 +153,13 @@ EvalResult eval(Node &ast, Memory &memory) {
                 Token identifierTok = get<Token>(node.children[0]);
                 string identifier = get<string>(identifierTok.data);
 
-                if (!memory_contains(memory, identifier)) throw RuntimeError("Unknown identifier \""+identifier+"\"", identifierTok.pos);
+                if (!memory.contains(identifier)) throw RuntimeError("Unknown identifier \""+identifier+"\"", identifierTok.pos);
 
-                EvalResult value = memory_get(memory, identifier);
+                EvalResult value = memory.get(identifier);
 
                 if (holds_alternative<int>(value)) {
-                    memory_update(memory, identifier, get<int>(value) - 1);
-                    return memory_get(memory, identifier);
+                    memory.update(identifier, get<int>(value) - 1);
+                    return memory.get(identifier);
                 }
                 else if (holds_alternative<monostate>(value)) {
                     throw RuntimeError("Accessing uninitialized identifier \""+identifier+"\"", identifierTok.pos);
@@ -164,12 +171,12 @@ EvalResult eval(Node &ast, Memory &memory) {
                 Token identifierTok = get<Token>(node.children[0]);
                 string identifier = get<string>(identifierTok.data);
 
-                if (!memory_contains(memory, identifier)) throw RuntimeError("Unknown identifier \""+identifier+"\"", identifierTok.pos);
+                if (!memory.contains(identifier)) throw RuntimeError("Unknown identifier \""+identifier+"\"", identifierTok.pos);
 
-                EvalResult value = memory_get(memory, identifier);
+                EvalResult value = memory.get(identifier);
 
-                if (holds_alternative<int>(memory_get(memory, identifier))) {
-                    memory_update(memory, identifier, get<int>(value) - 1);
+                if (holds_alternative<int>(memory.get(identifier))) {
+                    memory.update(identifier, get<int>(value) - 1);
                 }
                 else if (holds_alternative<monostate>(value)) {
                     throw RuntimeError("Accessing uninitialized identifier \""+identifier+"\"", identifierTok.pos);
@@ -188,9 +195,9 @@ EvalResult eval(Node &ast, Memory &memory) {
             case TokenType::Identifier: {
                 string identifier = get<string>(token.data);
                 
-                if (!memory_contains(memory, identifier)) throw RuntimeError("Unknown identifier \""+identifier+"\"", token.pos);
+                if (!memory.contains(identifier)) throw RuntimeError("Unknown identifier \""+identifier+"\"", token.pos);
 
-                EvalResult value = memory_get(memory, identifier);
+                EvalResult value = memory.get(identifier);
 
                 if (holds_alternative<monostate>(value)) throw RuntimeError("Accessing uninitialized identifier \""+identifier+"\"", token.pos);
                 
diff --git a/src/main.cpp b/src/main.cpp
index 204d6d0..b39b9b5 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -24,7 +24,7 @@ int main(int argc, char* argv[]) {
 
     vector<string> input;
     vector<Token> tokens;
-    Memory memory = new_memory();
+    Memory memory = Memory();
 
     while (true) {
         try {
diff --git a/src/memory.cpp b/src/memory.cpp
index 20c9868..b20ae52 100644
--- a/src/memory.cpp
+++ b/src/memory.cpp
@@ -2,18 +2,13 @@
 #include "include/memory.h"
 using namespace std;
 
-Memory new_memory(void) {
-    Memory memory;
-
-    memory.emplace_back();
-    memory.back().depth = 0;
-    memory.back().name = "global";
-
-    return memory;
+Memory::Memory(void) {
+    scopes.emplace_back();
+    scopes.back().depth = 0;
 }
 
-bool memory_contains(Memory& memory, string identifier) {
-    for (auto rit = memory.rbegin(); rit != memory.rend(); ++rit) {
+bool Memory::contains(string identifier) {
+    for (auto rit = scopes.rbegin(); rit != scopes.rend(); ++rit) {
         Scope& scope = *rit;
         if (scope.vars.contains(identifier)) return true;
     }
@@ -21,8 +16,24 @@ bool memory_contains(Memory& memory, string identifier) {
     return false;
 }
 
-EvalResult memory_get(Memory& memory, string identifier) {
-    for (auto rit = memory.rbegin(); rit != memory.rend(); ++rit) {
+bool Memory::contains_top(string identifier) {
+    Scope& top = scopes.back();
+    return top.vars.contains(identifier);
+}
+
+void Memory::add_scope(void) {
+    Scope& top = scopes.back();
+    scopes.emplace_back();
+    scopes.back().depth = top.depth + 1;
+}
+
+void Memory::remove_scope(void) {
+    scopes.pop_back();
+}
+
+
+EvalResult Memory::get(string identifier) {
+    for (auto rit = scopes.rbegin(); rit != scopes.rend(); ++rit) {
         Scope& scope = *rit;
         if (scope.vars.contains(identifier)) return scope.vars[identifier];
     }
@@ -30,13 +41,13 @@ EvalResult memory_get(Memory& memory, string identifier) {
     throw;
 }
 
-void memory_set(Memory& memory, string identifier, EvalResult value) {
-    Scope& top = memory.back();
+void Memory::declare(string identifier, EvalResult value) {
+    Scope& top = scopes.back();
     top.vars[identifier] = value;
 }
 
-void memory_update(Memory& memory, string identifier, EvalResult value) {
-    for (auto rit = memory.rbegin(); rit != memory.rend(); ++rit) {
+void Memory::update(string identifier, EvalResult value) {
+    for (auto rit = scopes.rbegin(); rit != scopes.rend(); ++rit) {
         Scope& scope = *rit;
         if (scope.vars.contains(identifier)) {
             scope.vars[identifier] = value;
@@ -45,4 +56,9 @@ void memory_update(Memory& memory, string identifier, EvalResult value) {
     }
     
     throw;
+}
+
+Scope& Memory::_debug_top(void) {
+    Scope& top = scopes.back();
+    return top;
 }
\ No newline at end of file
diff --git a/test/expr_arithmetiques.cpp b/test/expr_arithmetiques.cpp
index 4c8b373..766ab28 100644
--- a/test/expr_arithmetiques.cpp
+++ b/test/expr_arithmetiques.cpp
@@ -6,7 +6,7 @@
 #include "../src/include/interpreter.h"
 
 int execute(string s) {
-    Memory memory = new_memory();
+    Memory memory = Memory();
     vector<Token> tokens = tokenize({ s });
     Node ast = parse(tokens);
     EvalResult res = eval(ast, memory);
diff --git a/test/variables.cpp b/test/variables.cpp
index b3daff2..ce08e61 100644
--- a/test/variables.cpp
+++ b/test/variables.cpp
@@ -6,7 +6,7 @@
 #include "../src/include/interpreter.h"
 
 int execute(string s) {
-    Memory memory = new_memory();
+    Memory memory = Memory();
     vector<Token> tokens = tokenize({ s });
     Node ast = parse(tokens);
     EvalResult res = eval(ast, memory);