jeff kang javascript2 update

assignments/callbacks.js

@@ -0,0 +1,66 @@
+const items = ['Pencil', 'Notebook', 'yo-yo', 'Gum'];
+
+function firstItem(arr, cb) {
+  // firstItem passes the first item of the given array to the callback function.
+  cb(arr[0]);
+}
+firstItem(items, function(first){
+  console.log(first);
+})
+
+function getLength(arr, cb) {
+  // getLength passes the length of the array into the callback.
+  cb(arr.length)
+}
+getLength(items, function(length){
+  console.log(length);
+})
+
+function last(arr, cb) {
+  // last passes the last item of the array into the callback.
+  cb(arr[items.length-1])
+}
+last(items, function(minus1){
+  console.log(minus1);
+})
+
+function sumNums(x, y, cb) {
+  // sumNums adds two numbers (x, y) and passes the result to the callback.
+  cb(x + y);
+}
+sumNums(2, 4, function(check){
+console.log(check);
+})
+
+function multiplyNums(x, y, cb) {
+  // multiplyNums multiplies two numbers and passes the result to the callback.
+  cb(x * y);
+}
+multiplyNums(4,6, function(mult){
+  console.log(mult);
+})
+
+function contains(item, list, cb) {
+  // contains checks if an item is present inside of the given array/list.
+  // Pass true to the callback if it is, otherwise pass false.
+    for(i=0;i< list.length; i++){
+      if (item === list[i]){
+        cb(true);    
+  }
+}
+      cb(false);
+
+}
+contains("",items, function(test){
+  console.log(test);
+})
+
+
+
+/* STRETCH PROBLEM */
+
+function removeDuplicates(array, cb) {
+  // removeDuplicates removes all duplicate values from the given array.
+  // Pass the duplicate free array to the callback function.
+  // Do not mutate the original array.
+}

assignments/function-conversion.js

@@ -1,23 +1,39 @@
 // Take the commented ES5 syntax and convert it to ES6 arrow Syntax
 
 // let myFunction = function () {};
+let myyFunction = ()=>{};
 
 // let anotherFunction = function (param) {
 //   return param;
 // };
+let anotherFunction = param =>{return param}
 
 // let add = function (param1, param2) {
 //   return param1 + param2;
 // };
-// add(1,2);
 
-let subtract = function (param1, param2) {
-  return param1 - param2;
-};
-subtract(1,2); //?
+let add = (param1, param2) => {
+  return param1+param2;
+}
+add(1,2);
+
+// let subtract = function (param1, param2) {
+//   return param1 - param2;
+// };
+
+
+let subtract = (param1,param2) => {
+  return param1-param2
+}
+subtract(1,2);
+
 
 exampleArray = [1,2,3,4];
+
 // const triple = exampleArray.map(function (num) {
 //   return num * 3;
 // });
-// console.log(triple);
+// console.log(triple);
+
+let triple = exampleArray.map((num) => 
+ num *3);