implement the difference between the 'w' motion and 'dw' motion using the transition table in vi-word-dfa, rather than convoluted if-branching

fcore/normal-mode/make-normal-delete.sml

@@ -335,42 +335,10 @@ struct
         val {buffer, cursorIdx, ...} = app
 
         val buffer = LineGap.goToIdx (cursorIdx, buffer)
-        val high = Cursor.nextWord (buffer, cursorIdx, count)
-        val buffer = LineGap.goToIdx (high, buffer)
+        val high = Cursor.nextWordForDelete (buffer, cursorIdx, count)
+        val length = high - cursorIdx
       in
-        (* The Cursor.nextWord skips newlines in some cases,
-         * which makes sense for the 'w' move motion.
-         * However, we sometimes don't want to skip newlines when deleting.
-         * For example, when 'dw' is used on the last word in a line,
-         * the 'w' motion would go to the first character of the next line
-         * but the 'dw' motion should delete until the newline. *)
-        if high >= #textLength buffer then
-          let
-            val finish = #textLength buffer - 1
-            val buffer = LineGap.goToIdx (finish, buffer)
-            val length =
-              if Cursor.isCursorAtStartOfLine (buffer, finish) then
-                finish - cursorIdx
-              else
-                high - cursorIdx
-          in
-            deleteAndFinish (app, cursorIdx, length, buffer, time)
-          end
-        else if Cursor.isCursorAtStartOfLine (buffer, high) then
-          deleteAndFinish (app, cursorIdx, high - cursorIdx, buffer, time)
-        else
-          let
-            val beforeHigh = high - 1
-            val buffer = LineGap.goToIdx (beforeHigh, buffer)
-            val high =
-              if
-                Cursor.isCursorAtStartOfLine (buffer, beforeHigh)
-                andalso beforeHigh <> cursorIdx
-              then beforeHigh
-              else high
-          in
-            deleteAndFinish (app, cursorIdx, high - cursorIdx, buffer, time)
-          end
+        deleteAndFinish (app, cursorIdx, length, buffer, time)
       end
 
   fun deleteByDfa (app as {buffer, ...}: app_type, count, fMove, time) =