How to convert an ArrayList containing Integers to primitive int array?

If you are using java-8 there’s also another way to do this. int[] arr = list.stream().mapToInt(i -> i).toArray(); What it does is: getting a Stream<Integer> from the list obtaining an IntStream by mapping each element to itself (identity function), unboxing the int value hold by each Integer object (done automatically since Java 5) getting the … Read more

Add an element to an array in Swift

As of Swift 3 / 4 / 5, this is done as follows. To add a new element to the end of an Array. anArray.append(“This String”) To append a different Array to the end of your Array. anArray += [“Moar”, “Strings”] anArray.append(contentsOf: [“Moar”, “Strings”]) To insert a new element into your Array. anArray.insert(“This String”, at: … Read more

Difference between array_map, array_walk and array_filter

Changing Values: array_map cannot change the values inside input array(s) while array_walk can; in particular, array_map never changes its arguments. Array Keys Access: array_map cannot operate with the array keys, array_walk can. Return Value: array_map returns a new array, array_walk only returns true. Hence, if you don’t want to create an array as a result … Read more

Create an empty object in JavaScript with {} or new Object()?

Objects There is no benefit to using new Object(); – whereas {}; can make your code more compact, and more readable. For defining empty objects they’re technically the same. The {} syntax is shorter, neater (less Java-ish), and allows you to instantly populate the object inline – like so: var myObject = { title: ‘Frog’, … Read more