我正在努力学习Swift，想知道Apple对以下实验的预期答案，该答案在Apple的GuidedTour的错误处理部分提供。Playground如下；Experiment:Addcodetothrowanerrorinsidethedoblock.Whatkindoferrordoyouneedtothrowsothattheerrorishandledbythefirstcatchblock?Whataboutthesecondandthirdblocks?enumPrinterError:ErrorType{caseOutOfPapercaseNoTonercaseOnFire}f