diff --git a/src/node-obfuscators/NodeObfuscator.ts b/src/node-obfuscators/NodeObfuscator.ts
index 03f95f99..cc8c3c73 100644
--- a/src/node-obfuscators/NodeObfuscator.ts
+++ b/src/node-obfuscators/NodeObfuscator.ts
@@ -48,7 +48,7 @@ export abstract class NodeObfuscator implements INodeObfuscator {
      */
     protected replaceLiteralStringByArrayElement (nodeValue: string): string {
         let value: string = Utils.stringToUnicode(nodeValue),
-            unicodeArray = this.nodes.get('unicodeArrayNode').getNodeData(),
+            unicodeArray: string[] = this.nodes.get('unicodeArrayNode').getNodeData(),
             sameIndex: number = unicodeArray.indexOf(value),
             index: number;
 
diff --git a/src/node-obfuscators/VariableDeclarationObfuscator.js b/src/node-obfuscators/VariableDeclarationObfuscator.js
index 5b0d7461..3a3c853f 100644
--- a/src/node-obfuscators/VariableDeclarationObfuscator.js
+++ b/src/node-obfuscators/VariableDeclarationObfuscator.js
@@ -39,9 +39,12 @@ class VariableDeclarationObfuscator extends NodeObfuscator_1.NodeObfuscator {
         let isNodeAfterVariableDeclaratorFlag = false;
         estraverse.replace(scopeNode, {
             enter: (node, parentNode) => {
-                if (node.type === 'FunctionDeclaration' ||
-                    node.type === 'FunctionExpression' ||
-                    node.type === 'ArrowFunctionExpression') {
+                const functionNodes = [
+                    'ArrowFunctionExpression',
+                    'FunctionDeclaration',
+                    'FunctionExpression'
+                ];
+                if (functionNodes.indexOf(node.type) >= 0) {
                     estraverse.replace(node, {
                         enter: (node, parentNode) => {
                             this.replaceNodeIdentifierByNewValue(node, parentNode, this.variableNames);
diff --git a/src/node-obfuscators/VariableDeclarationObfuscator.ts b/src/node-obfuscators/VariableDeclarationObfuscator.ts
index 36e3d98b..02eeec7c 100644
--- a/src/node-obfuscators/VariableDeclarationObfuscator.ts
+++ b/src/node-obfuscators/VariableDeclarationObfuscator.ts
@@ -76,11 +76,13 @@ export class VariableDeclarationObfuscator extends NodeObfuscator {
 
         estraverse.replace(scopeNode, {
             enter: (node: ITreeNode, parentNode: ITreeNode) => {
-                if (
-                    node.type === 'FunctionDeclaration' ||
-                    node.type === 'FunctionExpression' ||
-                    node.type === 'ArrowFunctionExpression'
-                ) {
+                const functionNodes: string[] = [
+                    'ArrowFunctionExpression',
+                    'FunctionDeclaration',
+                    'FunctionExpression'
+                ];
+
+                if (functionNodes.indexOf(node.type) >= 0) {
                     estraverse.replace(node, {
                         enter: (node: ITreeNode, parentNode: ITreeNode) => {
                             this.replaceNodeIdentifierByNewValue(node, parentNode, this.variableNames);