2 files changed, 21 insertions, 4 deletions
diff --git a/lib/protocols/Evaluator.ml b/lib/protocols/Evaluator.ml
index 789fb9d..6a63431 100644
--- a/lib/protocols/Evaluator.ml
+++ b/lib/protocols/Evaluator.ml
@@ -1,5 +1,10 @@
+type kind = ..
+
 class type implementation = object
-  method invoke : Handle.t -> (Handle.t, Concepts.Condition.condition) result
+  method parse : string -> (kind, Concepts.Condition.condition) result
+
+  method eval :
+    kind -> Handle.t list -> within:Handle.t -> (Handle.t, Concepts.Condition.condition) result
 end
 
 type Handle.protocol += Evaluator of implementation
@@ -8,4 +13,5 @@ type t = implementation
 let make impl = Evaluator (impl :> implementation)
 let from handle = Handle.into handle (function Evaluator impl -> Some impl | _ -> None)
 let require = Handle.require from
-let invoke i program = Handle.invoke i (fun o -> o#invoke program)
+let parse i source = Handle.invoke i (fun o -> o#parse source)
+let eval i kind inputs ~within = Handle.invoke i (fun o -> o#eval kind inputs ~within)
diff --git a/lib/protocols/Evaluator.mli b/lib/protocols/Evaluator.mli
index 3d42b5c..934c5e3 100644
--- a/lib/protocols/Evaluator.mli
+++ b/lib/protocols/Evaluator.mli
@@ -1,10 +1,21 @@
 type t
+type kind = ..
 
 class type implementation = object
-  method invoke : Handle.t -> (Handle.t, Concepts.Condition.condition) result
+  method parse : string -> (kind, Concepts.Condition.condition) result
+
+  method eval :
+    kind -> Handle.t list -> within:Handle.t -> (Handle.t, Concepts.Condition.condition) result
 end
 
 val make : #implementation -> Handle.protocol
 val from : Handle.t -> t Handle.interface option
 val require : Handle.t -> (t Handle.interface, Concepts.Condition.condition) result
-val invoke : t Handle.interface -> Handle.t -> (Handle.t, Concepts.Condition.condition) result
+val parse : t Handle.interface -> string -> (kind, Concepts.Condition.condition) result
+
+val eval :
+  t Handle.interface ->
+  kind ->
+  Handle.t list ->
+  within:Handle.t ->
+  (Handle.t, Concepts.Condition.condition) result