-val register: uri:string -> url:string -> unit
-val update: unit -> HelmLogger.html_msg
-val getxml : ?format:encoding -> ?patch_dtd:bool -> string -> string
-val getxslt : ?patch_dtd:bool -> string -> string
-val getdtd : ?patch_dtd:bool -> string -> string
+
+val exists: string -> bool
+
+val getxml : string -> string
+val getxslt : string -> string
+val getdtd : string -> string