shorthand coding technique 🚀🚀

Author: lgope

js-coding-technique/mandatory-parameter.js

@@ -0,0 +1,18 @@
+// Longhand:
+
+function fooFunc(bar) {
+  if (bar === undefined) {
+    throw new Error('Missing parameter!');
+  }
+  return bar;
+}
+
+// Shorthand:
+
+mandatory = () => {
+  throw new Error('Missing parameter!');
+};
+
+fooFunc = (bar = mandatory()) => {
+  return bar;
+};

js-coding-technique/spread-operator.js

@@ -0,0 +1,30 @@
+// Longhand
+
+// joining arrays
+const odd = [1, 5, 9];
+const nums = [2, 4, 6].concat(odd);
+
+// cloning arrays
+const arr = [1, 2, 3, 4, 5, 6];
+const arr2 = arr.slice();
+
+// Shorthand:
+
+// joining arrays
+const odd = [1, 5, 9];
+const nums = [2, 4, 6, ...odd];
+console.log(nums); // [ 2, 4, 6, 1, 3, 5 ]
+
+// cloning arrays
+const arr = [1, 2, 3, 4, 5, 6];
+const arr2 = [...arr];
+
+// cloning arrays 1
+const odd = [1, 5, 9];
+const nums = [2, ...odd, 4, 6, 11, 17];
+
+// combine the spread operator with ES6 destructuring notation:
+const { a, b, ...z } = { a: 1, b: 2, c: 5, d: 6 };
+console.log(a); // 1
+console.log(b); // 2
+console.log(z); // { c: 5, d: 6 }