Class: EMPromise::Trampoline

Inherits:
Object
  • Object
show all
Defined in:
lib/em_promise.rb

Defined Under Namespace

Classes: SubmittedBlock

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(&initial_blk) ⇒ Trampoline

Returns a new instance of Trampoline.



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# File 'lib/em_promise.rb', line 21

def initialize(&initial_blk)
	@ready = true
	@fiber = Fiber.new { |blk|
		Thread.current[:_em_promise_trampoline] = self
		self.ready = false
		Trampoline.yield(blk.call)
	}
	@fiber.resume(&initial_blk) if initial_blk
end

Instance Attribute Details

#ready ⇒ Object

Returns the value of attribute ready.



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# File 'lib/em_promise.rb', line 9

def ready
  @ready
end

Class Method Details

.yield(arg = nil) ⇒ Object 



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# File 'lib/em_promise.rb', line 41

def self.yield(arg=nil)
	tramp = Thread.current[:_em_promise_trampoline]
	raise "Trampoline already ready?" if tramp&.ready

	loop do
		tramp&.ready = true
		blk = Fiber.yield arg
		tramp&.ready = false
		return arg unless blk.is_a?(SubmittedBlock)

		arg = blk.call
	end
end

Instance Method Details

#submit(&blk) ⇒ Object 



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# File 'lib/em_promise.rb', line 31

def submit(&blk)
	EM.next_tick do
		if ready
			@fiber.resume(SubmittedBlock.new(blk))
		else
			submit(&blk)
		end
	end
end