Functions and methods

As we discussed previously, functions and methods are self-contained chunks of code that work on a specific task. Note that the syntax of methods and functions is identical, so where I refer to functions in this section, I am also referring to methods. Let’s look at another example of a function:

String sayHello() {
  return "Hello world!";
}

This sayHello function structure is very similar to the main function we explored previously but also includes a return type of String, so the function must have a return statement at the end that returns a value of the expected type. In this example, the function returns a String literal of "Hello world!". If the function could return a String literal or null, then, as we saw in the Null safety section, we would mark the function’s return type as String.

Note that the function’s return type can be omitted because the Dart analyzer can infer the return type from the...