ephemeral relations as outputs of FOL and program overhaul

1 files changed, 0 insertions, 105 deletions

diff --git a/lib/evaluators/Lambda.ml b/lib/evaluators/Lambda.ml
deleted file mode 100644
index d864ca1..0000000
--- a/lib/evaluators/Lambda.ml
+++ /dev/null
@@ -1,105 +0,0 @@
-module Error = struct
-  open Concepts.Condition
-
-  let unknown_name name =
-    condition "unknown-name"
-      "A term named neither a bound variable nor a relation existing under this snapshot"
-      ("name" |=| Concepts.Value.String name)
-
-  let not_applicable () =
-    condition "not-applicable"
-      "A term was applied to an argument, but it denotes a relation rather than an abstraction"
-      empty
-
-  let unapplied_abstraction () =
-    condition "unapplied-abstraction"
-      "A program reduced to an abstraction, which names no relation to enumerate" empty
-
-  let cancelled () =
-    condition "evaluation-cancelled" "An evaluation was stopped before it produced its result" empty
-end
-
-(* A dummy untyped lambda calculus where constants are relations. We
-   look for a name in the environment first and resolved through the
-   context otherwise, so the relations reachable under the snapshot
-   are the outer environment every program is evaluated on *)
-type term = Name of string | Abstract of string * term | Apply of term * term
-type program = Program of term * Protocols.Directory.t Protocols.Handle.interface
-
-module Program = Protocols.Program.Make (struct
-  type t = program
-end)
-
-type value = Relation of Protocols.Handle.t | Closure of string * term * environment
-and environment = value BatMap.String.t
-
-(* let reduce context term = *)
-(*   let open Utilities.Result in *)
-(*   let rec eval environment term = *)
-(*     match context.Protocols.Context.status () with *)
-(*     | `Cancelled | `Exhausted -> Error (Error.cancelled ()) *)
-(*     | `Live -> *)
-(*        match term with *)
-(*        | Name name -> *)
-(*           begin match BatMap.String.find_opt name environment with *)
-(*            | Some value -> Ok value *)
-(*            | None -> *)
-(*               let* found = Runtime.Context.resolve context name in *)
-(*               let* handle = Option.to_result ~none:(Error.unknown_name name) found in *)
-(*               Ok (Relation handle) *)
-(*           end *)
-(*        | Abstract (binder, body) -> Ok (Closure (binder, body, environment)) *)
-(*        | Apply (operator, operand) -> *)
-(*           let* operator = eval environment operator in *)
-(*           match operator with *)
-(*           | Relation _ -> Error (Error.not_applicable ()) *)
-(*           | Closure (binder, body, closed) -> *)
-(*              let* argument = eval environment operand in *)
-(*              eval (BatMap.String.add binder argument closed) body *)
-(*   in *)
-(*   eval BatMap.String.empty term *)
-
-let reduce (Program (term, dir)) =
-  let open Utilities.Result in
-  let open Protocols in
-  let rec eval env term =
-    match term with
-    | Name name ->
-      begin match BatMap.String.find_opt name env with
-      | Some value -> Ok value
-      | None ->
-          let* handle =
-            Directory.find dir name |> fmap (Option.to_result ~none:(Error.unknown_name name))
-          in
-          Ok (Relation handle)
-      end
-    | Abstract (binder, body) -> Ok (Closure (binder, body, env))
-    | Apply (operator, operand) -> (
-        let* operator = eval env operator in
-        match operator with
-        | Relation _ -> Error (Error.not_applicable ())
-        | Closure (binder, body, closed) ->
-            let* argument = eval env operand in
-            eval (BatMap.String.add binder argument closed) body )
-  in
-  eval BatMap.String.empty term
-
-let execute term =
-  let open Utilities.Result in
-  let* value = reduce term in
-  match value with
-  | Closure _ -> Error (Error.unapplied_abstraction ())
-  | Relation handle ->
-      let* enumerable = Protocols.Enumerable.require handle in
-      Protocols.Enumerable.enumerate enumerable
-
-class evaluator =
-  object (self)
-    inherit Kernel.Lifecycle.null
-    inherit Kernel.Identity.of_id
-    method to_string = "lambda-evaluator"
-    method invoke program = execute program
-    method protocols : Protocols.Handle.protocol list = [Program.make self]
-  end
-
-let make () = new evaluator |> Protocols.Handle.make