describe "while assignment", ->
	it "should loop while value is truthy", ->
		counter = 0
		get_next = ->
			if counter < 3
				counter += 1
				counter
			else
				nil
		results = {}
		while val := get_next!
			table.insert results, val
		assert.same results, {1, 2, 3}

	it "should work with function results", ->
		counter = 0
		fn = ->
			counter += 1
			if counter <= 3
				counter * 10
			else
				nil

		sum = 0
		while val := fn!
			sum += val
		assert.same sum, 60 -- (10+20+30)

	it "should exit immediately on nil", ->
		get_val = -> nil
		counter = 0
		while val := get_val!
			counter += 1
		assert.same counter, 0

	it "should support break in loop", ->
		items = {1, 2, 3, 4, 5}
		sum = 0
		for item in *items
			sum += item
			break if sum > 6
		assert.same sum, 10