Return type for the method is missing processing.js - processing.js

Question

Hi i'm new to programming, and while i was trying to do an exercise this error poped up, and i have no idea what it means and how to fix it.
it's an example in the processing.js library that after i tried to copy didn't go so well.
Mover mover;
void setup(){
size (600,600);
mover = new Mover();
}
void draw(){
mover.update();
mover.display();
mover.checkEdges();
}
class Mover {
// position, velocity, and acceleration
PVector position;
PVector velocity;
PVector acceleration;
// Mass is tied to size
float mass;
Mover(float m, float x, float y) { //<<<the error occurs here
mass = m;
position = new PVector(x, y);
velocity = new PVector(0, 0);
acceleration = new PVector(0, 0);
}
// Newton's 2nd law: F = M * A
// or A = F / M
void applyForce(PVector force) {
// Divide by mass
PVector f = PVector.div(force, mass);
// Accumulate all forces in acceleration
acceleration.add(f);
}
void update() {
// Velocity changes according to acceleration
velocity.add(acceleration);
// position changes by velocity
position.add(velocity);
// We must clear acceleration each frame
acceleration.mult(0);
}
// Draw Mover
void display() {
stroke(255);
strokeWeight(2);
fill(255, 200);
ellipse(position.x, position.y, mass*16, mass*16);
}
// Bounce off bottom of window
void checkEdges() {
if (position.y > height) {
velocity.y *= -0.9; // A little dampening when hitting the bottom
position.y = height;
}
}
}

Answer 1

The only problem I see in your code is that your Mover constructor takes three arguments, but you're not giving it any in this line:
mover = new Mover();
So I'd fix that error before anything else. If you're still having problems, please be much more specific about exactly how you're compiling and running this code. Are you using the Processing editor? Which version? During exactly which step do you get an error?