diff --git a/misc/sexp.ml b/misc/sexp.ml
index 23cad624..1bbbaf0c 100644
--- a/misc/sexp.ml
+++ b/misc/sexp.ml
@@ -42,7 +42,7 @@ let hash a = Hashtbl.hash a
 let of_int x = Atom (string_of_int x)
 let of_float x = Atom (string_of_float x)
 let of_bool x = Atom (string_of_bool x)
-let of_string x = Atom x
+let atom x = Atom x
 let of_unit = List []
 let of_list l = List l
 let of_rev_list l = List (List.rev l)
diff --git a/misc/sexp.mli b/misc/sexp.mli
index 6e755918..0d095c9a 100644
--- a/misc/sexp.mli
+++ b/misc/sexp.mli
@@ -41,11 +41,12 @@ val equal : t -> t -> bool
 val compare : t -> t -> int
 val hash : t -> int
 
+val atom : string -> t  (** Build an atom directly from a string *)
+
 val of_int : int -> t
 val of_bool : bool -> t
 val of_list : t list -> t
 val of_rev_list : t list -> t  (** Reverse the list *)
-val of_string : string -> t
 val of_float : float -> t
 val of_unit : t
 val of_pair : t * t -> t