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|
(* TEST
expect;
*)
let pp fmt = Format.printf (fmt^^"@.")
type 'a box = B of 'a
(* Basic tests *)
module M = struct
type c = C
type t = {x : c box }
end
module N = struct
type d = D
let d = D
type t = {x: d box}
end
open N;;
[%%expect {|
val pp : ('a, Format.formatter, unit, unit, unit, unit) format6 -> 'a = <fun>
type 'a box = B of 'a
module M : sig type c = C type t = { x : c box; } end
module N : sig type d = D val d : d type t = { x : d box; } end
|}]
let f M.{ x=B C } y = M.C,y;;
let g M.(x) M.(w) = x * w
;;
let g = function
| M.[] -> []
| M.[C] -> M.[C]
| _ -> []
;;
let h = function
| M.[||] -> None
| M.[| C |] -> Some M.C
| _ -> None
;;
let f2 = function
| M.( B (B C) ) -> M.C
;;
(* () constructor *)
let M.() = ()
;;
[%%expect {|
val f : M.t -> 'a -> M.c * 'a = <fun>
val g : int -> int -> int = <fun>
val g : M.c list -> M.c list = <fun>
val h : M.c array -> M.c option = <fun>
val f2 : M.c box box -> M.c = <fun>
|}]
(* Pattern open separation*)
module L = struct
type _ c = C : unit c
type t = { t : unit c }
type r = { r : unit c }
let x ()= pp "Wrong value L.x"
end
;;
module K = struct
type _ c = C : unit c
type t = { t : unit c }
type r = { r : unit c }
let x ()= pp "Right value K.x"
end;;
[%%expect {|
module L :
sig
type _ c = C : unit c
type t = { t : unit c; }
type r = { r : unit c; }
val x : unit -> unit
end
module K :
sig
type _ c = C : unit c
type t = { t : unit c; }
type r = { r : unit c; }
val x : unit -> unit
end
|}]
let () =
let test =
let open K in
function
| L.{t}, ({r=C} : K.r) -> x ()
in
test (L.{t=C}, K.{r=C});;
[%%expect {|
Right value K.x
|}]
module Exterior = struct
module Gadt = struct
module Boolean = struct
type t = { b : bool }
type wrong = false | true
let print () = pp "Wrong function: Exterior.Gadt.Boolean.print"
end
type _ t =
| Bool : Boolean.t -> bool t
| Int : int -> int t
| Eq : 'a t * 'a t -> bool t
let print () = pp "Wrong function: Exterior.Gadt.print"
end
let print () = pp "Wrong function: Exterior.print"
end;;
[%%expect {|
module Exterior :
sig
module Gadt :
sig
module Boolean :
sig
type t = { b : bool; }
type wrong = false | true
val print : unit -> unit
end
type _ t =
Bool : Boolean.t -> bool t
| Int : int -> int t
| Eq : 'a t * 'a t -> bool t
val print : unit -> unit
end
val print : unit -> unit
end
|}]
let rec eval: type t. t Exterior.Gadt.t -> t = function
| Exterior.( Gadt.( Eq (a,b) ) ) -> (eval a) = (eval b)
| Exterior.( Gadt.( Bool Boolean.{b} ) ) -> b
| Exterior.Gadt.( Int n ) -> n
let () =
let print () = pp "Right function print" in
let choose (type a):a Exterior.Gadt.t * a Exterior.Gadt.t -> a -> a =
fun (a,b) c ->
match a, b, c with
| Exterior.( Gadt.( Bool Boolean.{b} ), Gadt.Bool _ , _ ) -> print(); true
| Exterior.(Gadt.Bool Gadt.Boolean.{b}), _ , true -> print(); true
| Exterior.(Gadt.Bool Gadt.Boolean.{b}), _ , false -> print(); b
| Exterior.Gadt.( Int n, Int k, 0 ) -> print(); 0
| Exterior.( Gadt.(Int n, Gadt.Int k, l) ) -> print(); k+n+l
| Exterior.Gadt.( Eq (a,b) ), _, true -> print(); true
| Exterior.(Gadt.( Eq (a,b), _ , false )) -> print(); eval a = eval b in
let _ =
choose Exterior.Gadt.(Bool Boolean.{b=true}, Bool Boolean.{b=false}) false
in
print ()
;;
[%%expect {|
val eval : 't Exterior.Gadt.t -> 't = <fun>
Right function print
Right function print
|}
]
(* existential type *)
module Existential = struct
type printable = E : 'a * ('a -> unit) -> printable
end
let rec print: Existential.printable -> unit = function
| Existential.( E(x, print) ) -> print x
;;
[%%expect {|
module Existential :
sig type printable = E : 'a * ('a -> unit) -> printable end
val print : Existential.printable -> unit = <fun>
|}]
(* Test that constructors and variables introduced in scope inside
M.(..) are not propagated outside of M.(..) *)
module S = struct
type 'a t = Sep : unit t
type ex = Ex: 'a * 'a -> ex
let s = Sep
end
;;
[%%expect {|
module S :
sig
type 'a t = Sep : unit t
type ex = Ex : 'a * 'a -> ex
val s : unit t
end
|}]
let test_separation = function
| S.(Sep), (S.(Sep,Sep), Sep) -> ();;
[%%expect {|
Line 2, characters 27-30:
2 | | S.(Sep), (S.(Sep,Sep), Sep) -> ();;
^^^
Error: Unbound constructor Sep
|}]
let test_separation_2 = function
| S.(Ex(a,b)), Ex(c,d) -> ();;
[%%expect {|
Line 2, characters 17-19:
2 | | S.(Ex(a,b)), Ex(c,d) -> ();;
^^
Error: Unbound constructor Ex
|}]
let test_separation_3 = function
| S.(Sep) -> s;;
[%%expect {|
Line 2, characters 15-16:
2 | | S.(Sep) -> s;;
^
Error: Unbound value s
|}]
(* Testing interaction of local open in pattern and backtracking *)
module PR6437 = struct
module Ctx = struct
type ('a, 'b) t =
| Nil : (unit, unit) t
| Cons : ('a, 'b) t -> ('a * unit, 'b * unit) t
end
module Var = struct
type 'a t =
| O : ('a * unit) t
| S : 'a t -> ('a * unit) t
end
end
let rec f : type g1 g2. (g1, g2) PR6437.Ctx.t * g1 PR6437.Var.t
-> g2 PR6437.Var.t = function
| PR6437.( Ctx.(Cons g), Var.(O) ) -> PR6437.Var.O
| PR6437.( Ctx.(Cons g), Var.(S n) ) -> PR6437.Var.S (f (g, n))
| _ -> . ;;
[%%expect {|
module PR6437 :
sig
module Ctx :
sig
type ('a, 'b) t =
Nil : (unit, unit) t
| Cons : ('a, 'b) t -> ('a * unit, 'b * unit) t
end
module Var :
sig type 'a t = O : ('a * unit) t | S : 'a t -> ('a * unit) t end
end
val f : ('g1, 'g2) PR6437.Ctx.t * 'g1 PR6437.Var.t -> 'g2 PR6437.Var.t =
<fun>
|}]
|
