# structual equivalence of resources
resource a
	op f(int x)
	const int x = 10
	op g() returns int  x
body a()
	proc f(z) { write("a's f",x,z) }
	proc g() returns z  { write("a's g",x); z = 2*x }
end
resource b
	op i(int x)
	op h() returns int  y
	type foo = rec(int a,b)
body b(int z)
	op j(int x)

	write("b",z)
	h(); i(19); j(87)

	proc h() returns y { write("h",z) ; y = 2*z }
	proc i(x) { write("b's i",x,z) }
	proc j(x) { write("b's j",x,z) }
end
resource main
	import a, b
body main()
	write("main starts")
	cap b  cb
	cb = create b(56)
	cb.i(87)
	cap a  ca
	ca = create a()
	ca.f(999)
	cb = ca
	cb.i(77)
end