1 files changed, 63 insertions, 0 deletions
diff --git a/library/libobject.ml b/library/libobject.ml
new file mode 100644
index 000000000..f5e610704
--- /dev/null
+++ b/library/libobject.ml
@@ -0,0 +1,63 @@
+
+(* $Id$ *)
+
+open Util
+open Names
+
+type 'a object_declaration = {
+  load_function : 'a -> unit;
+  cache_function : section_path * 'a -> unit;
+  specification_function : 'a -> 'a }
+
+type obj = Dyn.t (* persistent dynamic objects *)
+
+type dynamic_object_declaration = {
+  dyn_load_function : obj -> unit;
+  dyn_cache_function : section_path * obj -> unit;
+  dyn_specification_function : obj -> obj }
+
+let object_tag lobj = Dyn.tag lobj
+
+let cache_tab = 
+  (Hashtbl.create 17 : (string,dynamic_object_declaration) Hashtbl.t)
+
+let declare_object (na,odecl) =
+  let (infun,outfun) = Dyn.create na in
+  let loader lobj =
+    if Dyn.tag lobj = na then odecl.load_function (outfun lobj)
+    else anomaly "somehow we got the wrong dynamic object in the loadfun"
+  and cacher (spopt,lobj) =
+    if Dyn.tag lobj = na then odecl.cache_function(spopt,outfun lobj)
+    else anomaly "somehow we got the wrong dynamic object in the cachefun"
+  and spec_extractor lobj = 
+    infun(odecl.specification_function (outfun lobj))
+  in 
+  Hashtbl.add cache_tab na { dyn_load_function = loader;
+                             dyn_cache_function = cacher;
+                             dyn_specification_function = spec_extractor };
+  (infun,outfun)
+
+
+let load_object lobj =
+  let tag = object_tag lobj in
+  try 
+    let dodecl = Hashtbl.find cache_tab tag in 
+    dodecl.dyn_load_function lobj
+  with Not_found ->
+    anomaly ("Cannot find loadfun for an object with tag "^tag)
+
+let cache_object (spopt,lobj) =
+  let tag = object_tag lobj in
+  try 
+    let dodecl = Hashtbl.find cache_tab tag in 
+    dodecl.dyn_cache_function(spopt,lobj)
+  with Not_found ->
+    anomaly ("Cannot find cachefun for an object with tag "^tag)
+
+let extract_object_specification lobj =
+  let tag = object_tag lobj in
+  try 
+    let dodecl = Hashtbl.find cache_tab tag in
+    dodecl.dyn_specification_function lobj
+  with Not_found ->
+    anomaly ("Cannot find specification extractor for an object with tag "^tag)