Rename [Memo.t] to [Memo.Table.t] (#5576)

We're renaming [Memo.t] to [Memo.Table.t] and [Memo.Build.t] to [Memo.t] to make many type signatures in Dune shorter (and also not to bake in the notion of "builds" into the generic Memo library).

This is Step 1 of this renaming.

Signed-off-by: Andrey Mokhov <amokhov@janestreet.com>

src/dune_engine/action_builder0.ml

@@ -174,8 +174,8 @@ let fail x =
   x.fail ()
 
 type ('input, 'output) memo =
-  { lazy_ : ('input, 'output * Dep.Set.t) Memo.t Lazy.t
-  ; eager : ('input, 'output * Dep.Facts.t) Memo.t Lazy.t
+  { lazy_ : ('input, 'output * Dep.Set.t) Memo.Table.t Lazy.t
+  ; eager : ('input, 'output * Dep.Facts.t) Memo.Table.t Lazy.t
   }
 
 let create_memo name ~input ?cutoff ?human_readable_description f =

src/dune_engine/build_system.ml

@@ -289,10 +289,11 @@ and Exported : sig
      "Undefined_recursive_module" exception. *)
 
   val build_file_memo :
-    (Path.t, Import.Digest.t * Import.Digest.t Path.Build.Map.t option) Memo.t
+    (Path.t, Digest.t * Digest.t Path.Build.Map.t option) Memo.Table.t
     [@@warning "-32"]
 
-  val build_alias_memo : (Alias.t, Dep.Fact.Files.t) Memo.t [@@warning "-32"]
+  val build_alias_memo : (Alias.t, Dep.Fact.Files.t) Memo.Table.t
+    [@@warning "-32"]
 
   val dep_on_alias_definition :
     Rules.Dir_rules.Alias_spec.item -> unit Action_builder.t

src/dune_rules/dir_status.ml

@@ -65,7 +65,7 @@ let check_no_module_consumer stanzas =
 module DB = struct
   type nonrec t =
     { stanzas_per_dir : Dune_file.Stanzas.t Dir_with_dune.t Path.Build.Map.t
-    ; fn : (Path.Build.t, t) Memo.t
+    ; fn : (Path.Build.t, t) Memo.Table.t
     }
 
   let stanzas_in db ~dir = Path.Build.Map.find db.stanzas_per_dir dir

src/memo/memo.ml

@@ -1021,18 +1021,18 @@ module State = struct
         ]
 end
 
-type ('input, 'output) t =
-  { spec : ('input, 'output) Spec.t
-  ; cache : ('input, ('input, 'output) Dep_node.t) Store.t
-  }
+module Table = struct
+  type ('input, 'output) t =
+    { spec : ('input, 'output) Spec.t
+    ; cache : ('input, ('input, 'output) Dep_node.t) Store.t
+    }
+end
 
 module Stack_frame = struct
-  type ('input, 'output) memo = ('input, 'output) t
-
   include Stack_frame_without_state
 
   let as_instance_of (type i) (Dep_node_without_state.T t)
-      ~of_:(memo : (i, _) memo) : i option =
+      ~of_:(memo : (i, _) Table.t) : i option =
     match Type_eq.Id.same memo.spec.witness t.spec.witness with
     | Some Type_eq.T -> Some t.input
     | None -> None
@@ -1079,7 +1079,7 @@ let invalidate_dep_node (dep_node : _ Dep_node.t) =
 let invalidate_store = Store.iter ~f:invalidate_dep_node
 
 let create_with_cache (type i o) name ~cache ~input ~cutoff
-    ~human_readable_description (f : i -> o Fiber.t) =
+    ~human_readable_description (f : i -> o Fiber.t) : (i, o) Table.t =
   let spec =
     Spec.create ~name:(Some name) ~input ~cutoff ~human_readable_description f
   in
@@ -1097,7 +1097,7 @@ let create_with_store (type i) name
 let create (type i) name ~input:(module Input : Input with type t = i) ?cutoff
     ?human_readable_description f =
   (* This mutable table is safe: the implementation tracks all dependencies. *)
-  let cache = Store.of_table (Table.create (module Input) 2) in
+  let cache = Store.of_table (Stdune.Table.create (module Input) 2) in
   let input = (module Input : Store_intf.Input with type t = i) in
   create_with_cache name ~cache ~input ~cutoff ~human_readable_description f
 
@@ -1113,7 +1113,7 @@ let make_dep_node ~spec ~input : _ Dep_node.t =
       | No -> false)
   }
 
-let dep_node (t : (_, _) t) input =
+let dep_node (t : (_, _) Table.t) input =
   match Store.find t.cache input with
   | Some dep_node -> dep_node
   | None ->
@@ -1366,7 +1366,7 @@ end = struct
         | Error cycle_error -> raise (Cycle_error.E cycle_error))
 end
 
-let exec (type i o) (t : (i, o) t) i = Exec.exec_dep_node (dep_node t i)
+let exec (type i o) (t : (i, o) Table.t) i = Exec.exec_dep_node (dep_node t i)
 
 let dump_cached_graph ?(on_not_cached = `Raise) ?(time_nodes = false) cell =
   let rec collect_graph (Dep_node.T dep_node) graph : Graph.t Fiber.t =
@@ -1409,8 +1409,6 @@ let dump_cached_graph ?(on_not_cached = `Raise) ?(time_nodes = false) cell =
 let get_call_stack = Call_stack.get_call_stack_without_state
 
 module Invalidation = struct
-  type ('i, 'o) memo = ('i, 'o) t
-
   (* This is currently used only for informing the user about the reason for
      restarting a build. *)
   module Reason = struct
@@ -1532,7 +1530,7 @@ module Invalidation = struct
 
   let clear_caches ~reason = Leaf { kind = Clear_caches; reason }
 
-  let invalidate_cache ~reason { cache; _ } =
+  let invalidate_cache ~reason ({ cache; _ } : _ Table.t) =
     Leaf { kind = Clear_cache cache; reason }
 
   let invalidate_node ~reason (dep_node : _ Dep_node.t) =
@@ -1751,7 +1749,7 @@ module Perf_counters = struct
 end
 
 module For_tests = struct
-  let get_deps (type i o) (t : (i, o) t) inp =
+  let get_deps (type i o) (t : (i, o) Table.t) inp =
     match Store.find t.cache inp with
     | None -> None
     | Some dep_node -> (

src/memo/memo.mli

@@ -114,12 +114,13 @@ module Build : sig
   end
 end
 
-type ('input, 'output) t
+(** A table memoizing results of executing a function. *)
+module Table : sig
+  type ('input, 'output) t
+end
 
 (** A stack frame within a computation. *)
 module Stack_frame : sig
-  type ('input, 'output) memo = ('input, 'output) t
-
   type t
 
   val to_dyn : t -> Dyn.t
@@ -130,7 +131,7 @@ module Stack_frame : sig
 
   (** Checks if the stack frame is a frame of the given memoized function and if
       so, returns [Some i] where [i] is the argument of the function. *)
-  val as_instance_of : t -> of_:('input, _) memo -> 'input option
+  val as_instance_of : t -> of_:('input, _) Table.t -> 'input option
 
   val human_readable_description : t -> User_message.Style.t Pp.t option
 end
@@ -174,8 +175,6 @@ exception Non_reproducible of exn
     memoization runs. These sets can be combined into larger sets to then be
     passed to [reset]. *)
 module Invalidation : sig
-  type ('input, 'output) memo = ('input, 'output) t
-
   type t
 
   include Monoid.S with type t := t
@@ -211,7 +210,7 @@ module Invalidation : sig
   val clear_caches : reason:Reason.t -> t
 
   (** Invalidate all computations stored in a given [memo] table. *)
-  val invalidate_cache : reason:Reason.t -> _ memo -> t
+  val invalidate_cache : reason:Reason.t -> _ Table.t -> t
 
   (** A list of human-readable strings explaining the reasons for invalidation.
       The list is truncated to [max_elements] elements, with [max_elements = 1]
@@ -227,7 +226,7 @@ val reset : Invalidation.t -> unit
 module type Input = sig
   type t
 
-  include Table.Key with type t := t
+  include Stdune.Table.Key with type t := t
 end
 
 module Store : sig
@@ -266,12 +265,10 @@ end
     If the caller provides the [cutoff] equality check, we will use it to check
     if the function's output is the same as cached in the previous computation.
     If it's the same, we will be able to skip recomputing the functions that
-    depend on it. Note: by default Dune wipes all memoization caches on every
-    run, so this early cutoff optimisation is not effective. To override default
-    behaviour, run Dune with the flag [DUNE_WATCHING_MODE_INCREMENTAL=true].
+    depend on it.
 
     If [human_readable_description] is passed, it will be used when displaying
-    the memo stack to the user.
+    the Memo stack to the user.
 
     Running the computation may raise [Memo.Cycle_error.E] if a dependency cycle
     is detected. *)
@@ -281,7 +278,7 @@ val create :
   -> ?cutoff:('o -> 'o -> bool)
   -> ?human_readable_description:('i -> User_message.Style.t Pp.t)
   -> ('i -> 'o Build.t)
-  -> ('i, 'o) t
+  -> ('i, 'o) Table.t
 
 (** Like [create] but accepts a custom [store] for memoization. This is useful
     when there is a custom data structure indexed by keys of type ['i] that is
@@ -293,10 +290,10 @@ val create_with_store :
   -> ?cutoff:('o -> 'o -> bool)
   -> ?human_readable_description:('i -> User_message.Style.t Pp.t)
   -> ('i -> 'o Build.t)
-  -> ('i, 'o) t
+  -> ('i, 'o) Table.t
 
 (** Execute a memoized function. *)
-val exec : ('i, 'o) t -> 'i -> 'o Build.t
+val exec : ('i, 'o) Table.t -> 'i -> 'o Build.t
 
 (** Print the memoized call stack during execution. This is useful for debugging
     purposes. *)
@@ -314,8 +311,8 @@ val push_stack_frame :
   -> (unit -> 'a Build.t)
   -> 'a Build.t
 
+(** A single build run. *)
 module Run : sig
-  (** A single build run. *)
   type t
 
   module For_tests : sig
@@ -342,7 +339,7 @@ end
 
 (** Create a "memoization cell" that focuses on a single input/output pair of a
     memoized function. *)
-val cell : ('i, 'o) t -> 'i -> ('i, 'o) Cell.t
+val cell : ('i, 'o) Table.t -> 'i -> ('i, 'o) Cell.t
 
 val lazy_cell :
      ?cutoff:('a -> 'a -> bool)
@@ -510,7 +507,7 @@ module For_tests : sig
       by calling [get_deps] with the name and input used during execution.
 
       Returns [None] if the dependencies were not computed yet. *)
-  val get_deps : ('i, _) t -> 'i -> (string option * Dyn.t) list option
+  val get_deps : ('i, _) Table.t -> 'i -> (string option * Dyn.t) list option
 
   (** Forget all memoized values, forcing them to be recomputed on the next
       build run. *)