Safe property access in JavaScript

safe_object_access.js

// Takes the first value after the last true value
var reverseCoalesce1 = true && 555 && 123;
console.log(reverseCoalesce1); // 123

// If a value is null, it stops there
var reverseCoalesce2 = true && null && 123;
console.log(reverseCoalesce2); // null

// This is great for object access
var obj = {a: {b: {c: 2}}};
var reverseCoalesce3 = obj && obj.a && obj.a.b && obj.a.b.c;
console.log(reverseCoalesce3); // 2

// Trying to access a property that doesn't exist stops the chain--no errors!
var reverseCoalesce4 = obj && obj.a && obj.a.d && obj.a.d.c;
console.log(reverseCoalesce4); // undefined

Note that it doesn't work with the traditional falsey values (e.g., 0).