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src/lib/sedlexing.mli

@@ -45,7 +45,9 @@ exception MalFormed
         Uchars [a], a position [pos] and a code point count [n].  The
         function should put [n] code points or less in [a], starting at
         position [pos], and return the number of characters provided. A
-        return value of 0 means end of input. *)
+        return value of 0 means end of input. [bytes_per_char] argument is
+        optional. If unspecified, byte positions are the same as code point
+        position. *)
 val create :
   ?bytes_per_char:(Uchar.t -> int) ->
   (Uchar.t array -> int -> int -> int) ->
@@ -62,13 +64,16 @@ val set_position :
         returned {!Lexing.position} records. *)
 val set_filename : lexbuf -> string -> unit
 
-(** Create a lexbuf from a stream of Unicode code points. *)
+(** Create a lexbuf from a stream of Unicode code points. [bytes_per_char] is
+    optional. If unspecified, byte positions are the same as code point positions. *)
 val from_gen : ?bytes_per_char:(Uchar.t -> int) -> Uchar.t Gen.t -> lexbuf
 
-(** Create a lexbuf from an array of Unicode code points. *)
+(** Create a lexbuf from an array of Unicode code points. [bytes_per_char] is
+    optional. If unspecified, byte positions are the same as code point positions. *)
 val from_int_array : ?bytes_per_char:(Uchar.t -> int) -> int array -> lexbuf
 
-(** Create a lexbuf from an array of Unicode code points. *)
+(** Create a lexbuf from an array of Unicode code points. [bytes_per_char] is
+    optional. If unspecified, byte positions are the same as code point positions. *)
 val from_uchar_array :
   ?bytes_per_char:(Uchar.t -> int) -> Uchar.t array -> lexbuf