structs-members.ljs

let assert = require("assert");

extern describe, it, Math;

struct Point {
  int x, y;
  function Point (int x, int y) {
    this->x = x;
    this->y = y;
  }
  function toString() {
    return "{x: " + this->x + ", y: " + this->y + "}";
  }
  function distanceTo(Point * other) {
    let Line l (this->x, this->y, other->x, other->y);
    return l.getLength();
  }
}

struct Line {
  Point a, b;
  function Line (int x1, int y1, int x2, int y2) {
    this->a.x = x1;
    this->a.y = y1;
    this->b.x = x2;
    this->b.y = y2;
  }
  function float getLength() {
    let float dx = this->a.x - this->b.x;
    let float dy = this->a.y - this->b.y;
    return float(Math.sqrt(dx * dx + dy * dy));
  }
  function toString() {
    return "{" + this->a.toString() + " -> " + this->b.toString() + "}";
  }
}

function floatIsEqual(a, b) {
  let d = a - b;
  if (d < 0) {
    d *= -1;
  }
  return d < 0.001;
}

describe('Member Functions', function() {
  it('allocates structs on the heap and call methods', function () {
    let Point * p = new Point(1, 2);
    assert (p->toString() === "{x: 1, y: 2}");

    let Line * l = new Line(1, 2, 3, 4);
    assert (l->toString() === "{{x: 1, y: 2} -> {x: 3, y: 4}}");
    assert (floatIsEqual(l->getLength(), 2.8284271247461903));
  });

  it('allocates structs on the stack and call methods', function () {
    let Line l1 (1, 2, 3, 4), l2 (2, 3, 4, 5), *l3;
    assert (l1.toString() === "{{x: 1, y: 2} -> {x: 3, y: 4}}");
    assert (l1.a.toString() === "{x: 1, y: 2}");
    assert (l1.b.toString() === "{x: 3, y: 4}");
  });

  it('allocates structs on the stack and call methods', function () {
    for (let int i = 0; i < 10; i++) {
      let Point * k = new Point(1, 2);
      assert (k->toString() === "{x: 1, y: 2}");
    }

    for (let int i = 0; i < 10; i++) {
      let Point a (i, 1), b (i, 2);
      assert (a.distanceTo(&b) === 1);
    }
  });
});