After reading this, you will never check undefined in the same way again! — In JavaScript and TypeScript there are different methods for checking whether a variable is undefined. However, some methods are better than others. After reading this, you will never check undefined in the same way again! Resume

Introduction This guide will present to you the following Typescript’s operators and keywords that are too often forgotten : !! , is , in , as , ?. and ?? . Bang bang it shot me down Everyone known the logical operator! which perform a logical negation on the provided operand. Few people knows of it’s big…