8. FUNCTIONS
// The “idea” of a random number
var getRandomNumber = function() {
return Math.random();
}
// A random number
var rand = getRandomNumber.call();
(LAZINESS)
48. SIMPLER UNIT TESTS
MARBLE DIAGRAMS AS UNIT TESTS
it('should filter out even values', function() {
var source = hot('--0--1--2--3--4--|');
var expected = '-----1-----3-----|';
expectObservable(source.filter(x => x % 2 == 1)).toBe(expected);
});