+let _dottypes = ".types"
+let _types = "types",5
+let _ann = "ann",3
+let _dotann = ".ann"
+let _var = "var",3
+let _dotbody = ".body"
+let _con = "con",3
+let _ind = "ind",3
+let _xpointer = "#xpointer(1/"
+let _con3 = "con"
+let _var3 = "var"
+let _ind3 = "ind"
+let _ann3 = "ann"
+let _types5 = "types"
+let _xpointer8 = "xpointer"
+let _cic5 = "cic:/"
+
+let is_malformed suri =
+ try
+ if String.sub suri 0 5 <> _cic5 then true
+ else
+ let len = String.length suri - 5 in
+ let last5 = String.sub suri len 5 in
+ let last3 = String.sub last5 2 3 in
+ if last3 = _con3 || last3 = _var3 || last3 = _ind3 ||
+ last3 = _ann3 || last5 = _types5 || last5 = _dotbody then
+ false
+ else
+ try
+ let index = String.rindex suri '#' + 1 in
+ let xptr = String.sub suri index 8 in
+ if xptr = _xpointer8 then
+ false
+ else
+ true
+ with Not_found -> true
+ with Invalid_argument _ -> true
+
+(* hash conses an uri *)
+let uri_of_string suri =
+ try
+ MapStringsToUri.find suri !set_of_uri
+ with Not_found ->
+ if is_malformed suri then
+ raise (IllFormedUri suri)
+ else
+ let new_uri = suri, fresh_id () in
+ set_of_uri := MapStringsToUri.add suri new_uri !set_of_uri;
+ new_uri
+
+
+let strip_xpointer ((uri,_) as olduri) =
+ try
+ let index = String.rindex uri '#' in
+ let no_xpointer = String.sub uri 0 index in
+ uri_of_string no_xpointer
+ with
+ Not_found -> olduri
+
+let clear_suffix uri ?(pat2="",0) pat1 =
+ try
+ let index = String.rindex uri '.' in
+ let index' = index + 1 in
+ let suffix = String.sub uri index' (String.length uri - index') in
+ if fst pat1 = suffix || fst pat2 = suffix then
+ String.sub uri 0 index
+ else
+ uri
+ with
+ Not_found -> assert false
+
+let has_suffix uri (pat,n) =
+ try
+ let suffix = String.sub uri (String.length uri - n) n in
+ pat = suffix
+ with
+ Not_found -> assert false
+
+
+let cicuri_of_uri (uri, _) = uri_of_string (clear_suffix uri ~pat2:_types _ann)
+
+let annuri_of_uri (uri , _) = uri_of_string ((clear_suffix uri _ann) ^ _dotann)
+
+let uri_is_annuri (uri, _) = has_suffix uri _ann
+
+let uri_is_var (uri, _) = has_suffix uri _var
+
+let uri_is_con (uri, _) = has_suffix uri _con
+
+let uri_is_ind (uri, _) = has_suffix uri _ind
+
+let bodyuri_of_uri (uri, _) =
+ if has_suffix uri _con then
+ Some (uri_of_string (uri ^ _dotbody))