add Char.{of_int{,_exn},to_int} (close #95)

src/core/CCChar.ml

@@ -12,6 +12,10 @@ let compare = Char.compare
 let pp = Buffer.add_char
 let print = Format.pp_print_char
 
+let of_int_exn = Char.chr
+let of_int c = try Some (of_int_exn c) with _ -> None
+let to_int = Char.code
+
 let lowercase_ascii c =
   if c >= 'A' && c <= 'Z'
   then Char.unsafe_chr (Char. code c + 32)

src/core/CCChar.mli

@@ -17,5 +17,18 @@ val uppercase_ascii : t -> t
 (** See {!Char}
     @since 0.20 *)
 
+val of_int_exn : int -> t
+(** Alias to {!Char.chr}
+    @raise Invalid_argument if the int is not within [0,...,255]
+    @since NEXT_RELEASE *)
+
+val of_int : int -> t option
+(** Safe version of {!of_int}
+    @since NEXT_RELEASE *)
+
+val to_int : t -> int
+(** Alias to {!Char.code}
+    @since NEXT_RELEASE *)
+
 val pp : Buffer.t -> t -> unit
 val print : Format.formatter -> t -> unit