use magic to cast types to opaque attributes

5 files changed, 26 insertions, 40 deletions

diff --git a/bin/main.ml b/bin/main.ml
index adbf1dc..46bb9f1 100644
--- a/bin/main.ml
+++ b/bin/main.ml
@@ -3,9 +3,9 @@ let main () =
   print_endline digest
 
 let () =
-  (* TODO: Since the comparison on the standard function is done atop of the abstract value, a change on the abstract name incurs into an alteration of the order as well *)
-  let left_value: Relational_engine.Conventions.AbstractValue.t = {fields = Relational_engine.Conventions.AbstractValue.StringMap.of_list [("value!!!!!", "0")]} in
-  let right_value: Relational_engine.Conventions.AbstractValue.t = {fields = Relational_engine.Conventions.AbstractValue.StringMap.of_list [("value", "1")]} in
-  let tuple = Relational_engine.Tuple.make_materialized ~relation: "natural_less_than" ~attributes: (Relational_engine.Conventions.AbstractValue.StringMap.of_list [("left", left_value); ("right", right_value)]) in
-  print_endline @@ string_of_bool @@ Relational_engine.Prelude.Standard.less_than_natural.membership_criteria tuple;
+  let tuple = 
+    Relational_engine.Tuple.make_materialized 
+      ~relation: "natural_less_than"
+      ~attributes: (Relational_engine.Tuple.AttributeMap.of_list [("left", Obj.magic 0); ("right", Obj.magic 1)])
+  in print_endline @@ string_of_bool @@ Relational_engine.Prelude.Standard.less_than_natural.membership_criteria tuple;
   main ()
diff --git a/lib/attribute.ml b/lib/attribute.ml
index 05d33f4..27214b0 100644
--- a/lib/attribute.ml
+++ b/lib/attribute.ml
@@ -1,21 +1,14 @@
-type t = {
-  hash : Conventions.Hash.t;
-  name : Conventions.Name.t;
-  name_hash : Conventions.Hash.t;
-  value : Conventions.AbstractValue.t;
-  value_hash : Conventions.Hash.t;
-}
+type referenced = { value_hash : Conventions.Hash.t }
 
-type materialized = {
-  name: Conventions.Name.t;
-  value: Conventions.AbstractValue.t
-}
+type materialized = { value: Conventions.AbstractValue.t }
 
-let make ~name ~value =
-  let name_hash = Conventions.Hash.hash_text name in
-  let value_hash = Conventions.AbstractValue.hash_text value in
-  let hash = Conventions.Hash.hash_text (name_hash ^ value_hash) in
-  { hash; name; name_hash; value; value_hash }
+type t = 
+  | Referenced of referenced
+  | Materialized of materialized
 
-let make_with_hashes ~hash ~name ~name_hash ~value ~value_hash =
-  { hash; name; name_hash; value; value_hash }
+let make_referenced ~value =
+  let value_hash = Conventions.AbstractValue.hash value in
+  Referenced { value_hash }
+
+let make_materialized ~value =
+  Materialized { value }
\ No newline at end of file
diff --git a/lib/conventions.ml b/lib/conventions.ml
index 74f6cc3..538bc5c 100644
--- a/lib/conventions.ml
+++ b/lib/conventions.ml
@@ -13,14 +13,6 @@ module Cardinality = struct
 end
 
 module AbstractValue = struct
-  module StringMap = Map.Make(String)
-  type t = {
-    fields: string StringMap.t;
-  }
-  let hash_text value = 
-    let folder (name: string) (value: string) (acc: Hash.t) = 
-      Hash.(hash_text (acc ^ hash_text name ^ hash_text value))
-    in StringMap.fold folder value.fields ""
-  let compare a b = 
-    StringMap.compare String.compare a.fields b.fields
+  type t = Obj.t
+  let hash (elem: t) = Interop.Sha256.compute_hash @@ Marshal.to_bytes elem []
 end
\ No newline at end of file
diff --git a/lib/prelude/standard.ml b/lib/prelude/standard.ml
index 43ffc44..d6f8cf3 100644
--- a/lib/prelude/standard.ml
+++ b/lib/prelude/standard.ml
@@ -10,11 +10,12 @@ let less_than_natural: Relation.t =
       (left, r) in
     match position with
     | Some position -> 
-      let (left: Conventions.AbstractValue.t), (right: Conventions.AbstractValue.t) =
-        let (left_value, right_value) = pair_of_nat position in
-        ({ fields = Conventions.AbstractValue.StringMap.of_list [("value", string_of_int left_value)] }, 
-         { fields = Conventions.AbstractValue.StringMap.of_list [("value", string_of_int right_value)] })
-      in let attributes: Conventions.AbstractValue.t Tuple.AttributeMap.t =
+      let left, right = pair_of_nat position in
+      (* let left: Attribute.t = Attribute.make_materialized ~value: (Obj.magic left) in *)
+      (* let right: Attribute.t = Attribute.make_materialized ~value: (Obj.magic right) in *)
+      let left = Obj.magic left in
+      let right = Obj.magic right in
+      let attributes: Attribute.materialized Tuple.AttributeMap.t =
         Tuple.AttributeMap.of_list [("left", left); ("right", right)]
       in Generator.Value (Tuple.make_materialized ~relation: "less_than" ~attributes: attributes, generator)
     | None -> Error "Cannot produce a randomly enumerated value for less_than over naturals."
diff --git a/lib/tuple.ml b/lib/tuple.ml
index 07632db..3c11fba 100644
--- a/lib/tuple.ml
+++ b/lib/tuple.ml
@@ -3,12 +3,12 @@ module AttributeMap = Map.Make(String)
 type non_materialized = {
   hash : Conventions.Hash.t;
   relation : Conventions.Name.t;
-  attributes : Conventions.Hash.t AttributeMap.t;
+  attributes : Attribute.referenced AttributeMap.t;
 }
 
 type materialized = {
   relation: Conventions.Name.t;
-  attributes: Conventions.AbstractValue.t AttributeMap.t
+  attributes: Attribute.materialized AttributeMap.t
 }
 
 type t =