local A   = Local("A", Type)
local a   = Local("a", A)
local vec = Const("vec")
local A1  = Local("A", vec(A))
local a1  = Local("a", a)
local T   = Const("T")
print(Pi(A, a, A1, a1, a1))
local t = mk_pi("A", Type, mk_pi("a", Var(0), mk_pi("A", vec(Var(1)), mk_pi("a", Var(0), T(Var(0), Var(2))))))
print(t)