   #
   showMarker: (linkMarker, matchingCharCount) ->
     linkMarker.style.display = ""
-    # TODO(philc):
     for j in [0...linkMarker.childNodes.length]
       if (j < matchingCharCount)
         linkMarker.childNodes[j].classList.add("matchingCharacter")

      deactivate()
      callback?()

alphabetHints =
  activateOnEnter: false
  hintKeystrokeQueue: []
  logXOfBase: (x, base) -> Math.log(x) / Math.log(base)

  fillInMarkers: (hintMarkers) ->
    hintStrings = @hintStrings(hintMarkers.length)

  # 'callback' is invoked (if it is provided).
  deactivateMode: (delay, callback) ->
    deactivate = =>
      DomUtils.removeElement @hintMarkerContainingDiv if @hintMarkerContainingDiv
      @hintMarkerContainingDiv = null
      @markerMatcher = null
      @isActive = false
      @hintMode?.exit()
      @hintMode = null
