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|
(*
dune exec examples/filtering.exe <<EOF
{
"id": "398eb027",
"name": "John Doe",
"pages": [
{
"id": 1,
"title": "The Art of Flipping Coins",
"url": "http://example.com/398eb027/1"
},
{ "id": 2, "deleted": true },
{
"id": 3,
"title": "Artichoke Salad",
"url": "http://example.com/398eb027/3"
},
{
"id": 4,
"title": "Flying Bananas",
"url": "http://example.com/398eb027/4"
}
]
}
EOF
*)
open Yojson.Basic.Util
let extract_titles json =
[ json ] |> filter_member "pages" |> flatten |> filter_member "title"
|> filter_string
let main () =
let json = Yojson.Basic.from_channel stdin in
List.iter print_endline (extract_titles json)
let () = main ()
|
