ts-object-utils

Best way to check for null or undefined in typescript using a type guard. Other types also supported. Can strip out null or undefine or complex types like T | null etc.
npm install --save ts-object-utils
To use:

import ObjectUtil from "ts-object-utils";

let a: number | null = 0;

console.log(a*4); //Error: a might be null

if(!ObjectUtil.isNullOrUndefined(a)){
    console.log(a*4); //Works
}