indexOf is used to search for a value or reference inside of an array. In this lesson we first look at what values are returned when a search is successful vs when it's unsuccessful. Then we move onto a technique that shows how to use the return valu…
Sort can automatically arrange items in an array. In this lesson we look at the basics including how to sort an array of strings alphabetically and the correct way to perform a numerical sort on an array of numbers. We finish as always with a practic…
Array filter creates a new array with all elements that pass the test implemented by the provided function. In this lesson we discuss how only a truthy or falsey value is required as the return value to the function, which in turns allows us to be cr…
Array slice creates a shallow copy of an array. In this lesson we cover, in detail, exactly what a 'shallow' copy is and how it can trip people up. We go on to look at examples that show to how to copy only the first item, the last item and even how…
Array push is used to add elements to the end of an Array. In this lesson we'll see how the push method accepts multiple arguments, can be used to merge two arrays,. Push can accept multi args: const pets = ["dog", "hamster"]; pets.pus…
some returns a boolean value after passing each item in the source array through the test function that you pass in as the first parameter. This makes it well suited to the types of queries that require a simple yes or no answer. In this lesson we lo…
