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open! Core
let%expect_test _ =
let x = 5 in
let value, string = [%demo x + 10] in
print_endline string;
print_endline "==========";
print_endline (Int.to_string value);
[%expect {|
x + 10
==========
15
|}]
;;
module M = struct
type 'a t = T of 'a
let of_int (x : int) = T x
let of_string (x : string) = T x
module Let_syntax = struct
module Let_syntax = struct
let bind (T x) ~f = f x
let map (T x) ~f = T (f x)
end
end
end
let%expect_test _ =
let T value, string =
[%demo
let%bind.M pos =
let%map.M a = M.of_int 70 in
a
in
let%bind.M long_string =
M.of_string
"xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx \
contents xxxxx"
in
let%map.M len = M.of_int 8 in
String.sub long_string ~pos ~len |> fun x -> x]
in
print_endline string;
print_endline "==========";
print_endline value;
[%expect
{|
let%bind.M pos =
let%map.M a = M.of_int 70 in
a
in
let%bind.M long_string =
M.of_string
"xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx xxxxx \
contents xxxxx"
in
let%map.M len = M.of_int 8 in
String.sub long_string ~pos ~len |> fun x -> x
==========
contents
|}]
;;
let%expect_test "demoing a module's structure" =
let module Example =
[%demo
let x = 1
module T = struct
type t =
| Foo
| Bar
[@@deriving sexp]
let a = Foo
let b = Bar
end]
in
let x = Example.x in
let a = Example.T.a in
let b = Example.T.b in
print_s [%message (x : int) (a : Example.T.t) (b : Example.T.t)];
[%expect {| ((x 1) (a Foo) (b Bar)) |}];
print_endline Example.ppx_demo_string;
[%expect
{|
let x = 1
module T = struct
type t =
| Foo
| Bar
[@@deriving sexp]
let a = Foo
let b = Bar
end
|}]
;;