diff --git a/dist/src/node-groups/DebugProtectionNodesGroup.js b/dist/src/node-groups/DebugProtectionNodesGroup.js
index eeef1501..9c2496d2 100644
--- a/dist/src/node-groups/DebugProtectionNodesGroup.js
+++ b/dist/src/node-groups/DebugProtectionNodesGroup.js
@@ -8,16 +8,8 @@ class DebugProtectionNodesGroup extends NodesGroup_1.NodesGroup {
     constructor(options = {}) {
         super(options);
         this.debugProtectionFunctionIdentifier = Utils_1.Utils.getRandomVariableName();
-        this.nodes = new Map([
-            [
-                'debugProtectionFunctionNode',
-                new DebugProtectionFunctionNode_1.DebugProtectionFunctionNode(this.debugProtectionFunctionIdentifier)
-            ],
-            [
-                'debugProtectionFunctionCallNode',
-                new DebugProtectionFunctionCallNode_1.DebugProtectionFunctionCallNode(this.debugProtectionFunctionIdentifier)
-            ]
-        ]);
+        this.nodes.set('debugProtectionFunctionNode', new DebugProtectionFunctionNode_1.DebugProtectionFunctionNode(this.debugProtectionFunctionIdentifier));
+        this.nodes.set('debugProtectionFunctionCallNode', new DebugProtectionFunctionCallNode_1.DebugProtectionFunctionCallNode(this.debugProtectionFunctionIdentifier));
         if (this.options['debugProtectionInterval']) {
             this.nodes.set('debugProtectionFunctionIntervalNode', new DebugProtectionFunctionIntervalNode_1.DebugProtectionFunctionIntervalNode(this.debugProtectionFunctionIdentifier));
         }
diff --git a/dist/src/node-groups/NodesGroup.js b/dist/src/node-groups/NodesGroup.js
index cd7576d4..b6edb8b5 100644
--- a/dist/src/node-groups/NodesGroup.js
+++ b/dist/src/node-groups/NodesGroup.js
@@ -1,6 +1,7 @@
 "use strict";
 class NodesGroup {
     constructor(options = {}) {
+        this.nodes = new Map();
         this.options = options;
     }
     getNodes() {
diff --git a/dist/src/node-groups/UnicodeArrayNodesGroup.js b/dist/src/node-groups/UnicodeArrayNodesGroup.js
index 8fde68cb..7ac8d030 100644
--- a/dist/src/node-groups/UnicodeArrayNodesGroup.js
+++ b/dist/src/node-groups/UnicodeArrayNodesGroup.js
@@ -11,12 +11,7 @@ class UnicodeArrayNodesGroup extends NodesGroup_1.NodesGroup {
         this.unicodeArrayRotateValue = Utils_1.Utils.getRandomInteger(100, 500);
         this.unicodeArrayTranslatorName = Utils_1.Utils.getRandomVariableName(UnicodeArrayNode_1.UnicodeArrayNode.UNICODE_ARRAY_RANDOM_LENGTH);
         let unicodeArrayNode = new UnicodeArrayNode_1.UnicodeArrayNode(this.unicodeArrayName, this.unicodeArrayRotateValue), unicodeArray = unicodeArrayNode.getNodeData();
-        this.nodes = new Map([
-            [
-                'unicodeArrayNode',
-                unicodeArrayNode
-            ]
-        ]);
+        this.nodes.set('unicodeArrayNode', unicodeArrayNode);
         if (this.options['wrapUnicodeArrayCalls']) {
             this.nodes.set('unicodeArrayCallsWrapper', new UnicodeArrayCallsWrapper_1.UnicodeArrayCallsWrapper(this.unicodeArrayTranslatorName, this.unicodeArrayName, unicodeArray));
         }
diff --git a/src/node-groups/DebugProtectionNodesGroup.ts b/src/node-groups/DebugProtectionNodesGroup.ts
index 63a7550b..a587b316 100644
--- a/src/node-groups/DebugProtectionNodesGroup.ts
+++ b/src/node-groups/DebugProtectionNodesGroup.ts
@@ -20,16 +20,14 @@ export class DebugProtectionNodesGroup extends NodesGroup {
     constructor (options: IOptions = {}) {
         super(options);
 
-        this.nodes = new Map <string, ICustomNode> ([
-            [
-                'debugProtectionFunctionNode',
-                new DebugProtectionFunctionNode(this.debugProtectionFunctionIdentifier)
-            ],
-            [
-                'debugProtectionFunctionCallNode',
-                new DebugProtectionFunctionCallNode(this.debugProtectionFunctionIdentifier)
-            ]
-        ]);
+        this.nodes.set(
+            'debugProtectionFunctionNode',
+            new DebugProtectionFunctionNode(this.debugProtectionFunctionIdentifier)
+        );
+        this.nodes.set(
+            'debugProtectionFunctionCallNode',
+            new DebugProtectionFunctionCallNode(this.debugProtectionFunctionIdentifier)
+        );
 
         if (this.options['debugProtectionInterval']) {
             this.nodes.set(
diff --git a/src/node-groups/NodesGroup.ts b/src/node-groups/NodesGroup.ts
index 6860974f..bec371ee 100644
--- a/src/node-groups/NodesGroup.ts
+++ b/src/node-groups/NodesGroup.ts
@@ -7,7 +7,7 @@ export abstract class NodesGroup implements INodesGroup {
     /**
      * @type {Map<string, Node>}
      */
-    protected nodes: Map <string, ICustomNode>;
+    protected nodes: Map <string, ICustomNode> = new Map <string, ICustomNode> ();
 
     /**
      * @type {IOptions}
diff --git a/src/node-groups/UnicodeArrayNodesGroup.ts b/src/node-groups/UnicodeArrayNodesGroup.ts
index a821a7bf..dd2dfefb 100644
--- a/src/node-groups/UnicodeArrayNodesGroup.ts
+++ b/src/node-groups/UnicodeArrayNodesGroup.ts
@@ -35,12 +35,10 @@ export class UnicodeArrayNodesGroup extends NodesGroup {
             ),
             unicodeArray: string [] = unicodeArrayNode.getNodeData();
 
-        this.nodes = new Map <string, ICustomNode> ([
-            [
-                'unicodeArrayNode',
-                unicodeArrayNode
-            ]
-        ]);
+        this.nodes.set(
+            'unicodeArrayNode',
+            unicodeArrayNode
+        );
 
         if (this.options['wrapUnicodeArrayCalls']) {
             this.nodes.set(