Remove unnecessary parts of Pgx_aux

- Option was added to Stdlib
- List.iteri, String.concat, and String.init exist
- String.starts_with was unused

pgx/src/pgx.ml

@@ -810,7 +810,7 @@ module Make (Thread : Io) = struct
             | Message_in.CommandComplete _ -> loop ()
             | Message_in.EmptyQueryResponse -> loop ()
             | Message_in.DataRow fields ->
-              List.map (Option.bind Value.of_string) fields |> f >>= loop
+              List.map (fun v -> Option.bind v Value.of_string) fields |> f >>= loop
             | Message_in.NoData -> loop ()
             | Message_in.ParameterStatus _ ->
               (* 43.2.6: ParameterStatus messages will be generated whenever
@@ -969,7 +969,7 @@ module Make (Thread : Io) = struct
       | _, Message_in.CopyData row -> loop acc ([ row |> Value.of_string ] :: rows) state
       | _, Message_in.CopyDone -> loop acc rows state
       | `Rows, Message_in.DataRow row ->
-        let row = List.map (Option.bind Value.of_string) row in
+        let row = List.map (fun v -> Option.bind v Value.of_string) row in
         loop acc (row :: rows) `Rows
       | (`Row_desc | `Rows), Message_in.CommandComplete _ ->
         let rows = List.rev rows in

pgx/src/pgx_aux.ml

@@ -1,23 +1,6 @@
 module String = struct
   include String
 
-  let starts_with str prefix =
-    let len = length prefix in
-    if length str < len
-    then false
-    else (
-      let rec aux i =
-        if i >= len
-        then true
-        else if unsafe_get str i <> unsafe_get prefix i
-        then false
-        else aux (i + 1)
-      in
-      aux 0)
-  ;;
-
-  let join = concat
-
   let implode xs =
     let buf = Buffer.create (List.length xs) in
     List.iter (Buffer.add_char buf) xs;
@@ -29,36 +12,6 @@ module String = struct
     let rec loop i accum = if i = len then accum else loop (i + 1) (f accum str.[i]) in
     loop 0 init
   ;;
-
-  (* Only available in the standard library since OCaml 4.02 *)
-  let init n f =
-    let s = Bytes.create n in
-    for i = 0 to n - 1 do
-      Bytes.unsafe_set s i (f i)
-    done;
-    Bytes.to_string s
-  ;;
-end
-
-module Option = struct
-  include Option
-
-  let equal ?(cmp = ( = )) a b =
-    match a, b with
-    | None, None -> true
-    | Some a, Some b -> cmp a b
-    | _ -> false
-  ;;
-
-  let map f = function
-    | Some v -> Some (f v)
-    | None -> None
-  ;;
-
-  let bind f = function
-    | Some v -> f v
-    | None -> None
-  ;;
 end
 
 module List = struct
@@ -99,16 +52,7 @@ module List = struct
       if res <> 0 then res else compare compare_elt xs ys
   ;;
 
-  let iteri f xs =
-    let rec loop i = function
-      | [] -> ()
-      | hd :: tl ->
-        f i hd;
-        loop (i + 1) tl
-    in
-    loop 0 xs
-  ;;
-
+  (* The default List.map isn't tail recursive so we replace it with one that is *)
   let map f xs = List.rev_map f xs |> List.rev
 end
 

pgx/src/pgx_aux.mli

@@ -3,26 +3,13 @@
 module String : sig
   include module type of String
 
-  val starts_with : string -> string -> bool
-  val join : string -> string list -> string
   val implode : char list -> string
   val fold_left : ('a -> char -> 'a) -> 'a -> string -> 'a
-  val init : int -> (int -> char) -> string
-end
-
-module Option : sig
-  include module type of Option
-
-  val equal : ?cmp:('a -> 'a -> bool) -> 'a option -> 'a option -> bool
-  val map : ('a -> 'b) -> 'a option -> 'b option
-  val bind : ('a -> 'b option) -> 'a option -> 'b option
 end
 
 module List : sig
   include module type of List
 
-  val iteri : (int -> 'a -> unit) -> 'a list -> unit
-
   (** Like the built-in [List.map], but tail-recursive *)
   val map : ('a -> 'b) -> 'a list -> 'b list
 end

pgx/src/pgx_value.ml

@@ -21,7 +21,7 @@ let required f = function
   | None -> raise (Conversion_failure "Expected not-null but got null")
 ;;
 
-let opt = Option.bind
+let opt f v = Option.bind v f
 let null = None
 
 let of_binary b =
@@ -100,7 +100,7 @@ let of_hstore hstore =
     in
     key_str ^ "=>" ^ value_str
   in
-  Some (String.join ", " (List.map string_of_mapping hstore))
+  Some (String.concat ", " (List.map string_of_mapping hstore))
 ;;
 
 let to_hstore' str =