Logical operators

short-circuit-operator.js

'use strict'

function f1 () {
  console.log('f1 called');
  return false;
}

function f2 () {
  console.log('f2 called');
  return true;
}

// Short Circuit operator && - That is, f2() is not evaluated if f1() is false, both functions must return boolean
var f3 = f1() && f2(); // f1 called

// Short Circuit operator && - That is, f2() is not evaluated if f1() is true, both functions must return boolean
var f4 = f1() || f2(); // f1 called \n f2 called