-a^2 in {1, 2, 3} |> f

has = "foo" in { "bar", "foo" }

if a in {1} and b in {2, 3, 4}
	print a, b, c

if a in [1,] and b in [2, 3, 4]
	print a, b, c

do
	exist = item in list
	check item in list

do
	item = get!
	exist = item in list
	check item in list

do
	item = get!
	list = {1, 2, 3}
	list = [1, 2, 3]
	not_exist = item not in list
	check item in list
	check item in {1, 2, 3}
	check item in [1, 2, 3]
	check item(...) in {[1]: 1, [2]: 2, [3]: 3}

do
	check -> x in tb
	check -> x not in tb
	local x, tb
	check -> return x in tb
	check -> x not in tb

do
	f1 = ->
		a = 2
		a in [
			1
			2
			3
			4
		]
	f2 = ->
		a not in [
			1
			2
			3
			4
		]
	f3 = ->
		a = 2
		a in { b, c, d
			e, f
			g
		}
	f4 = ->
		a = 2
		b = a in [ 1, 2
			3, 4
		]
	f5 = ->
		a = 2
		return a in [ 1, 2
			3, 4
		]
	f6 = ->
		b = a not in {
			1
			2
			x: 3
		}
	print a in []
	a = 1
	print a in {}

do
	a = 1
	print a in [1, 2, 1]

do
	a = -1
	print a in [-1, 11, 2, -1, 0, -1]

do
	a = 1
	b = 1
	print a in [b, 10, b]

do
	print x in ["", ""]
	print 1 in [1, 2, 1]

nil