Method: Concurrent::MVar#modify

Defined in:
lib/concurrent-ruby/concurrent/mvar.rb

#modify(timeout = nil) ⇒ Object

Atomically ‘take`, yield the value to a block for transformation, and then `put` the transformed value. Returns the transformed value. A timeout can be set to limit the time spent blocked, in which case it returns `TIMEOUT` if the time is exceeded.

Returns:

  • (Object) —

    the transformed value, or ‘TIMEOUT`

Raises:

  • (ArgumentError) 


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# File 'lib/concurrent-ruby/concurrent/mvar.rb', line 123

def modify(timeout = nil)
  raise ArgumentError.new('no block given') unless block_given?

  @mutex.synchronize do
    wait_for_full(timeout)

    # If we timed out we'll still be empty
    if unlocked_full?
      value = @value
      @value = yield value
      @full_condition.signal
      apply_deref_options(value)
    else
      TIMEOUT
    end
  end
end