so-js-example.js

/*
float xPosition; float yPosition,yPosition2,yPosition3,yPosition4;

void setup(){ 
  size(500,500);
  smooth();
  noStroke();
  yPosition=600;
  yPosition2=600;
  yPosition3=600;
  yPosition4=600;
}

void draw(){
  background(0);
  fill(#FF0000);
  ellipse(xPosition+100,yPosition,50,50);
  ellipse(xPosition+200,yPosition2,50,50);
  ellipse(xPosition+300,yPosition3,50,50);
  ellipse(xPosition+400,yPosition4,50,50);
  yPosition-=10;
  yPosition2-=5;
  yPosition3-=20;
  yPosition4-=15;
}
*/

var xPosition, yPosition, yPosition2, yPosition3, yPosition4; //all variables without assignment evaluate to `undefined`

function setup() {
  size(500, 500);
  smooth();
  noStroke();
  yPosition = yPosition2 = yPosition3 = yPosition4 = 600;
}

function draw() {
  background(0);
  fill('#FF0000');
  ellipse(xPosition + 100, yPosition, 50, 50);
  ellipse(xPosition + 200, yPosition2, 50, 50);
  ellipse(xPosition + 300, yPosition3, 50, 50);
  ellipse(xPosition + 400, yPosition4, 50, 50);
  yPosition -= 10;
  yPosition2 -= 5;
  yPosition3 -= 20;
  yPosition4 -= 15;
}