Add linked list implementation in JavaScript

Author: samps01

.gitignore

@@ -1,4 +1,6 @@
 .DS_Store
 
+.idea
+
 # Dependencies
 node_modules/

linked_list/javascript/linked_list_in_js.js

@@ -0,0 +1,98 @@
+//Implementing Linked List and it's method in Javascript (ES5)
+
+function Node(data){
+    this.data = data;
+    this.next = null;
+}
+
+function LinkedList(){
+    this._length = 0;
+    this.head = null;
+}
+
+LinkedList.prototype.isEmpty = function(){
+    if(this.head===null){
+        return true;
+    }else{
+        return false;
+    }
+}
+
+LinkedList.prototype.add = function(data){
+
+    if(!data){
+        console.error("No data found");
+    }else{
+        if(this.head === null){
+            this.head = new Node(data);
+        }else{
+            var newHead = new Node(data);
+            newHead.next = this.head;
+            this.head = newHead;
+        }
+    }
+    this._length++;
+}
+
+LinkedList.prototype.contains = function(data){
+    var current = this.head;
+    while(current !== null){
+        if(current.data === data){
+            return true;
+        }
+        current = current.next;
+    }
+    return false;
+}
+
+LinkedList.prototype.addAt = function(data,where){
+    var current = this.head;
+    var prev = null;
+    var newNode = new Node(data);
+    //debugger
+    while(current.data !== where){
+        prev = current;
+        current = current.next;
+    }
+    //prev.next = newNode;
+    //newNode.next = current;
+    var something = current.next;
+    current.next = newNode;
+    newNode.next = something;
+
+
+}
+
+LinkedList.prototype.append= function(data){
+    var current = this.head;
+    while(current.next !== null){
+        current = current.next;
+    }
+    current.next = new Node(data);
+    this._length++;
+}
+
+LinkedList.prototype.delete = function(data){
+    var current = this.head;
+    var prev = null;
+    if(this.head.data === data){
+        this.head = this.head.next;
+        this._length--;
+        return;
+    }
+    while(current.data !== data){
+        prev = current;
+        current = current.next;
+    }
+    prev.next = current.next;
+    this._length--;
+}
+var list = new LinkedList()
+list.add(10);
+list.add(20);
+list.add(30);
+list.add(40);
+list.append(50);
+list.addAt(15,20)
+console.log(list.contains(20));
+console.log(list)