+ (** see {! Http_constants.server_string} *)
+val server_string: string
+
+ (** pretty print an HTTP version *)
+val string_of_version: version -> string
+
+ (** parse an HTTP version from a string
+ @raise Invalid_HTTP_version if given string doesn't represent a supported HTTP
+ version *)
+val version_of_string: string -> version
+
+ (** pretty print an HTTP method *)
+val string_of_method: meth -> string
+
+ (** parse an HTTP method from a string
+ @raise Invalid_HTTP_method if given string doesn't represent a supported
+ method *)
+val method_of_string: string -> meth
+
+ (** converts an integer HTTP status to the corresponding status value
+ @raise Invalid_code if given integer isn't a valid HTTP status code *)
+val status_of_code: int -> status
+
+ (** converts an HTTP status to the corresponding integer value *)
+val code_of_status: [< status] -> int
+
+ (** @return true on "informational" status codes, false elsewhere *)