Make class get all functions of p5.js

p5.js Coding Questions
1

When creating a class I cannot make it so the class gets all the functions of p5.js library.
Can anyone help me?
it says fill is not defined
code :

var game = function(g) {

g.setup = function() {
    g.createCanvas(400,400);
    g.background(0);
    g.snake = new Snake();
    g.snake.test();
}

}
class Snake {

test() {
    fill(255);   //this line throws error (Uncaught ReferenceError: fill is not defined) 
    ellipse(0,0,100);  }

}
var mySnake = new p5(game);

2

It doesn’t seem you’re trying to expand p5js’ API, but rather you wanna access its API from inside your class, right?

If you’re using the instance mode style approach:

Your classes are gonna need to request the current sketch’s p5 reference in their constructor, something like this:

class Snake {
  constructor(p) {
    this.p = p || p5.instance;
  }

  display() {
    const { p } = this;
    p.fill(0xff).circle(p.width - 50 >> 1, p.height - 50 >> 1, 100);
    return this;
  }
}

new p5(p => {
  let snake;

  p.setup = () => {
    p.createCanvas(400, 400);
    snake = new Snake(p);
  };

  p.draw = () => {
    p.background(0);
    snake.display();
  };
});

Here’s a more complete online sketch to show you better how it works: