Higher order Functions

[Stan-breaks]

In this stage, you'll add support for higher order functions in your phaeton

For example, if test.phn contains the following

var globalGreeting = "Hello";

fun makeGreeter() {
  fun greet(name) {
    print globalGreeting + " " + name;
  }
  return greet;
}

var sayHello = makeGreeter();
sayHello("Bob");

The tester will run your program like this:

$ ./your_program.sh run test.phn
Hello Bob