Move validation to a `print` function

Signed-off-by: Rudi Grinberg <rudi.grinberg@gmail.com>

src/stdune/sexp.ml

@@ -296,13 +296,13 @@ module Of_sexp = struct
   let string = plain_string (fun ~loc:_ x -> x)
   let int =
     basic "Integer" (fun s ->
-      match int_of_string (s Atom.Dune) with
+      match int_of_string s with
       | x -> Ok x
       | exception _ -> Result.Error ())
 
   let float =
     basic "Float" (fun s ->
-      match float_of_string (s Atom.Dune) with
+      match float_of_string s with
       | x -> Ok x
       | exception _ -> Result.Error ())
 

src/usexp/atom.ml

@@ -29,8 +29,9 @@ let is_valid_jbuild str =
   not (loop (len - 1))
 
 let of_string s = A s
+let to_string (A s) = s
 
-let to_string (A t) syntax =
+let print (A t) syntax =
   match syntax with
   | Jbuild ->
     if is_valid_jbuild t then

src/usexp/atom.mli

@@ -5,8 +5,9 @@ type syntax = Jbuild | Dune
 val is_valid_dune : string -> bool
 
 val of_string : string -> t
+val to_string : t -> string
 
-val to_string : t -> syntax -> string
+val print : t -> syntax -> string
 
 val of_int : int -> t
 val of_float : float -> t

src/usexp/usexp.ml

@@ -90,13 +90,13 @@ let quoted s =
   Bytes.unsafe_to_string s'
 
 let rec to_string = function
-  | Atom a -> Atom.to_string a Atom.Dune
+  | Atom a -> Atom.print a Atom.Dune
   | Quoted_string s -> quoted s
   | List l -> Printf.sprintf "(%s)" (List.map l ~f:to_string |> String.concat ~sep:" ")
 
 let rec pp ppf = function
   | Atom s ->
-    Format.pp_print_string ppf (Atom.to_string s Atom.Dune)
+    Format.pp_print_string ppf (Atom.print s Atom.Dune)
   | Quoted_string s ->
     Format.pp_print_string ppf (quoted s)
   | List [] ->
@@ -137,7 +137,7 @@ let pp_print_quoted_string ppf s =
     Format.pp_print_string ppf (quoted s)
 
 let rec pp_split_strings ppf = function
-  | Atom s -> Format.pp_print_string ppf (Atom.to_string s Atom.Dune)
+  | Atom s -> Format.pp_print_string ppf (Atom.print s Atom.Dune)
   | Quoted_string s -> pp_print_quoted_string ppf s
   | List [] ->
     Format.pp_print_string ppf "()"

src/usexp/usexp.mli

@@ -12,8 +12,7 @@ module Atom : sig
   val is_valid_dune : string -> bool
 
   val of_string : string -> t
-
-  val to_string : t -> syntax -> string
+  val to_string : t -> string
 
   val of_int : int -> t
   val of_float : float -> t