mxUndoManager.prototype.undo=function(){for(;0<this.indexOfNextAdd;){var a=this.history[--this.indexOfNextAdd];a.undo();if(a.isSignificant()){this.fireEvent(new mxEventObject(mxEvent.UNDO,"edit",a));break}}};mxUndoManager.prototype.canRedo=function(){return this.indexOfNextAdd<this.history.length};