example.txt

Point:
    x, y, z f64

Particle:
    position, velocity, acceleration Point
    mass f64

particles = SoA(Particle, 100)
particles.position = random(0.03, 0.03)
particles.mass = 1e-6

time_step = 0.08
time_limit = 365.25
time = 0.0
while time < time_limit using particles:
    position += velocity * time_step/2

    for this, others in iter_pairs(particles):
        d = this.position - others.position
        r = sqrt(d.x^2 + d.y^2 + d.z^2)
        this.acceleration = -G/r^3 * others.mass * d

    time += time_step

    velocity += acceleration * time_step
    position += velocity * time_step/2