Channel#empty?/full? gone

Help & Support
1

We have an existing code base that relies on Channel#full? and Channel#empty? but those methods are gone in 0.31.0. For example, in one part of the code we only want to fsync a file when the incoming queue is empty:

loop do
  file.write_bytes ch.receive
  file.fsync if ch.empty?
end

Is there a technical difficulty to re-implement the methods? Or do any one have suggestions on how to work around that?

2
3

This is what I did:

class Channel(T)
  def full?
    if queue = @queue
      return queue.size >= @capacity
    end

    !@senders.empty?
  end

  def empty?
    if queue = @queue
      return queue.empty?
    end

    @senders.empty?
  end
end

But others have pointed out that it’s not thread safe.

4

I cannot find the PR for this. What was the reason to remove it. It looks like it was removed around the time MT was merged in.

5

It was removed for the MT support. Let’s follow this discussion in Restoring Channel#full?