-val reason_phrase_of_code: int -> string
-val reason_phrase_of_status: [< Http_types.status] -> string
+val string_of_version: version -> string
+val version_of_string: string -> version
+
+val string_of_method: meth -> string
+val method_of_string: string -> meth
+
+val status_of_code: int -> status
+val code_of_status: [< status] -> int