import java.util.ArrayList;

class CentreText {
  float[] coords;
  String text;
  float font_size;

  float text_width;

  CentreText(String txt, int size, float x, float y) {
    coords = new float[] {x, y};
    text = txt;
    font_size = size;

    textSize(font_size);
    text_width = textWidth(text);
  }

  void changeFontSize(float size) {
    font_size = size;
    textSize(font_size);
    text_width = textWidth(text);
  }

  void displayText() {
    fill(#000000);
    text(text, coords[0] - (text_width / 2), coords[1] + (font_size / 3));

class Button { ... }
class MyButton extends Button {
    void didClick() { ... }
}

void print() {
    println("Hello");
}

    public Button(Callable<Void> func) {
        this.func = func;
    }

and then to call:

     func.call();

def print_thing():
  print("...")
foo = print_thing
foo()

a->b->(g->g((a-b+1)|>a)/g(1|>b))(n->n.map(Math.fib).reduce((*)))

*(2,3)|>println
6\n