class Rooibos::Command::Wait

A one-shot timer command.

Applications need timed events. Notification auto-dismissal, debounced search, and animation frames all depend on delays. Building timers from scratch with threads is error-prone. Cancellation is tricky.

This command waits, then sends a message. It responds to cancellation cooperatively. When canceled, it sends Message::Canceled so you know the timer stopped.

Use it for delayed actions, debounced inputs, or animation loops.

Prefer the Command.wait or Command.tick factory methods for convenience. Both are aliases for the same behavior.

Example: Notification dismissal

def update(msg, model)
  case msg
  in :save_clicked
    [model.with(notification: "Saved!"), Command.wait(3.0, :dismiss)]
  in :dismiss
    [model.with(notification: nil), nil]
  in Message::Canceled
    [model.with(notification: nil), nil]  # User navigated away
  end
end

Example: Animation loop

def update(msg, model)
  case msg
  in :start_animation
    [model.with(frame: 0), Command.tick(0.1, :animate)]
  in :animate
    frame = (model.frame + 1) % 10
    [model.with(frame:), Command.tick(0.1, :animate)]
  end
end

Public Instance Methods

call (out, token)

Source

# File lib/rooibos/command/wait.rb, line 67
def call(out, token)
  start_time = Time.now
  timer_cancellation, _origin = Concurrent::Cancellation.timeout(seconds)
  combined = token.join(timer_cancellation)
  combined.origin.wait

  if token.canceled?
    out.put(Message::Canceled.new(command: self))
  else
    elapsed = Time.now - start_time
    response = Message::Timer.new(envelope:, elapsed:)
    out.put(Ractor.make_shareable(response))
  end
end

Executes the timer.

Waits for seconds, then sends TimerResponse. If canceled, sends Message::Canceled instead.

out: Outlet for sending messages.
token: Cancellation token from the runtime.

rooibos_cancellation_grace_period ()

Source

# File lib/rooibos/command/wait.rb, line 56
def rooibos_cancellation_grace_period
  0
end

Cooperative cancellation needs no grace period. The command responds instantly to cancellation via Concurrent::Cancellation.timeout.