enum Foo(Zero, One(x:Int), Two(x:Int, y:Int), Three(x:Int, y:Text, z:Bool), Four(x,y,z,w:Int), Last(t:Text))

func choose_text(f:Foo)->Text:
	>> f
	when f is Zero:
		return "Zero"
	is One(one):
		return "One: {one}"
	is Two(x, y):
		return "Two: x={x}, y={y}"
	is Three(three):
		return "Three: {three}"
	is Four:
		return "Four"
	else:
		return "else: {f}"

func main():
	>> Foo.Zero
	= Foo.Zero
	>> Foo.One(123)
	= Foo.One(x=123)
	>> Foo.Two(123, 456)
	= Foo.Two(x=123, y=456)

	>> Foo.One(10) == Foo.One(10)
	= yes

	>> Foo.One(10) == Foo.Zero
	= no

	>> Foo.One(10) == Foo.One(-1)
	= no

	>> Foo.One(10) < Foo.Two(1, 2)
	= yes

	>> x := Foo.One(123)
	>> t := {x:"found"; default="missing"}
	>> t[x]
	= "found"
	>> t[Foo.Zero]
	= "missing"

	>> choose_text(Foo.Zero)
	= "Zero"
	>> choose_text(Foo.One(123))
	= "One: 123"
	>> choose_text(Foo.Two(123, 456))
	= "Two: x=123, y=456"
	>> choose_text(Foo.Three(123, "hi", yes))
	= "Three: Three(x=123, y=\"hi\", z=yes)"
	>> choose_text(Foo.Four(1,2,3,4))
	= "Four"
	>> choose_text(Foo.Last("XX"))
	= "else: Foo.Last(t=\"XX\")"