Class: Reacto::Operations::Take

Inherits:
Object
  • Object
show all
Defined in:
lib/reacto/operations/take.rb

Instance Method Summary collapse

Constructor Details

#initialize(how_many_to_take) ⇒ Take

Returns a new instance of Take.



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# File 'lib/reacto/operations/take.rb', line 6

def initialize(how_many_to_take)
  if how_many_to_take < 0
    raise ArgumentError.new('Attempt to take negative size!')
  end

  @how_many_to_take = how_many_to_take
  @taken = 0
  @closed = false
end

Instance Method Details

#call(tracker) ⇒ Object



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# File 'lib/reacto/operations/take.rb', line 16

def call(tracker)
  behaviour = lambda do |value|
    return if @closed
    if @taken < @how_many_to_take
      tracker.on_value(value)
      @taken += 1
    else
      @closed = true
      tracker.on_close
    end
  end

  Subscriptions::OperationSubscription.new(
    tracker,
    value: behaviour
  )
end