class Button

	sig ClickHandler(sender as Object, args as EventArgs)

	event click as ClickHandler

	def receiveMouseClick1
		# pretend it's always in our bounds and we're enabled
		raise .click, this, EventArgs()  # .warning. unnecessary "this"
	
	def receiveMouseClick2
		raise .click, EventArgs()

	def receiveMouseClick3
		raise .click, this  # .warning. unnecessary "this"

	def receiveMouseClick4
		raise .click


class Program

	shared

		var _butt as Button
		var _clickCount = 0
		
		def main
			butt = _butt = Button()

			listen butt.click, ref .handleClick
			assert .clickCount == 0

			butt.receiveMouseClick1
			assert .clickCount == 1

			butt.receiveMouseClick2
			assert .clickCount == 2

			butt.receiveMouseClick3
			assert .clickCount == 3

			butt.receiveMouseClick4
			assert .clickCount == 4

		get clickCount from var

		def handleClick(sender as Object, args as EventArgs)
			assert sender is _butt
			assert (args to dynamic?) inherits EventArgs
			_clickCount += 1