       callback = anchor
 
     normalized = @_normalizeArgs 'foldUp', [0, anchor, {}]
-    return if not normalized
+    return unless normalized
     anchor = normalized[1]
     @isFoldedUp = true
     limit = @panels[anchor].length - 1


  accordion: (angle, anchor, options) ->
    normalized = @_normalizeArgs 'accordion', arguments
    return if not normalized
    [angle, anchor, options] = normalized

    for panel, i in @panels[anchor]

    @accordion angle / 10, anchor, options


  curl: (angle, anchor, options) ->
    normalized = @_normalizeArgs 'curl', arguments
    return unless normalized
    [angle, anchor, options] = normalized
    angle /=  @_getPanelType anchor

