[Header]

let (|>) g f = f g

let l1 = [1]
let l2 = [2]
let l3 = [3]
let l4 = [4]

let empty = IntListQ.emptyQ
let enQ v q = IntListQ.enQ (q, v)
let deQ q = let _, rq = IntListQ.deQ q in rq
let deQV q = let v, _ = IntListQ.deQ q in v

[Test]
IntListQ.deQ IntListQ.emptyQ

[Exception]
IntListQ.EMPTY_Q

[Test]
empty
|> enQ l1
|> deQV

[Value]
l1

[Test]
empty 
|> enQ l1
|> enQ l2
|> deQ
|> deQV

[Value]
l2

[Test]
empty
|> enQ l1
|> enQ l2
|> deQ
|> enQ l3
|> enQ l4
|> deQ
|> deQV

[Value]
l3

[Test]
empty
|> enQ l1
|> deQ
|> enQ l2
|> enQ l3
|> deQ
|> enQ l4
|> deQ
|> deQV

[Value]
l4


[Test]
empty |> enQ l1 |> enQ l2 |> enQ l3 |> enQ l4 |> deQ |> deQV

[Value]
l2

[Test]
empty |> enQ l1 |> enQ l2 |> enQ l3 |> enQ l4 |> deQ |> enQ l1 |> deQ |> enQ l2 |> deQ |> deQV

[Value]
l4

[Test]
empty |> enQ l1 |> enQ l3 |> deQ |> enQ l4 |> deQ |> deQV

[Value]
l4

[Test]
empty |> enQ l4 |> enQ l2 |> deQ |> deQ |> deQV

[Exception]
IntListQ.EMPTY_Q

[Test]
IntListQ.emptyQ |> enQ l1 |> enQ l2 |> deQV

[Value]
l1