use concurrency for rebuilding search list after deletion so we don't block main thread on very, very large files

shell/search-thread.sml

@@ -0,0 +1,14 @@
+structure SearchThread =
+struct
+  open CML
+
+  (* Prerequisite to sending message: move buffer to end. *)
+  fun loop (searchMailbox, inputMailbox) =
+    let
+      val (buffer, searchString) = Mailbox.recv searchMailbox
+      val (_, searchList) = SearchList.build (buffer, searchString)
+      val () = Mailbox.send (inputMailbox, InputMsg.WITH_SEARCH_LIST searchList)
+    in
+      loop (searchMailbox, inputMailbox)
+    end
+end

shell/shell.sml

@@ -6,6 +6,7 @@ struct
   (* create mailboxes for CML communication *)
   val inputMailbox = Mailbox.mailbox ()
   val drawMailbox = Mailbox.mailbox ()
+  val searchMailbox = Mailbox.mailbox ()
 
   fun frameBufferSizeCallback (width, height) =
     Mailbox.send (inputMailbox, RESIZE_EVENT (width, height))
@@ -79,7 +80,9 @@ struct
 
       val _ = CML.spawn (fn () => GlDraw.loop (drawMailbox, window))
       val _ = CML.spawn (fn () =>
-        UpdateThread.loop (app, inputMailbox, drawMailbox))
+        UpdateThread.loop (app, inputMailbox, drawMailbox, searchMailbox))
+      val _ = CML.spawn (fn () =>
+        SearchThread.loop (searchMailbox, inputMailbox))
     in
       ()
     end

shell/update-thread.sml

@@ -4,18 +4,21 @@ struct
   open MailboxType
   open InputMsg
 
-  fun sendMsg (msg, drawMailbox) =
-    case msg of DRAW msg => Mailbox.send (drawMailbox, msg)
+  fun sendMsg (msg, drawMailbox, searchMailbox) =
+    case msg of
+      DRAW msg => Mailbox.send (drawMailbox, msg)
+    | SEARCH (buffer, searchString) =>
+        Mailbox.send (searchMailbox, (buffer, searchString))
 
-  fun sendMsgs (msgList, drawMailbox) =
+  fun sendMsgs (msgList, drawMailbox, searchMailbox) =
     case msgList of
       hd :: tl =>
-        let val _ = sendMsg (hd, drawMailbox)
-        in sendMsgs (tl, drawMailbox)
+        let val _ = sendMsg (hd, drawMailbox, searchMailbox)
+        in sendMsgs (tl, drawMailbox, searchMailbox)
         end
     | [] => ()
 
-  fun loop (app: AppType.app_type, inputMailbox, drawMailbox) =
+  fun loop (app: AppType.app_type, inputMailbox, drawMailbox, searchMailbox) =
     let
       val inputMsg = Mailbox.recv inputMailbox
       val () =
@@ -33,8 +36,8 @@ struct
       val app = AppUpdate.update (app, inputMsg)
                 handle e => ExceptionLogger.log e
 
-      val () = sendMsgs (#msgs app, drawMailbox)
+      val () = sendMsgs (#msgs app, drawMailbox, searchMailbox)
     in
-      loop (app, inputMailbox, drawMailbox)
+      loop (app, inputMailbox, drawMailbox, searchMailbox)
     end
 end