Source file mediatype.ml

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open Cohttp

let media_match (_, (range, _)) (type_, _) =
  let type_, subtype =
    match Re.Str.(split (regexp "/") type_) with
    | [x; y] -> x, y
    | _      -> assert false
  in
  let open Accept in
  match range with
  | AnyMedia                     -> true
  | AnyMediaSubtype type_'       -> type_' = type_
  | MediaType (type_', subtype') -> type_' = type_ && subtype' = subtype
;;

let match_header provided header =
  let ranges =
    try Accept.(media_ranges header |> qsort)
    with Parsing.Parse_error -> []
  in
  let rec loop = function
    | [] -> None
    | r::rs ->
      try Some(List.find (media_match r) provided)
      with Not_found -> loop rs
  in
  loop ranges
;;