Although this may at first seem like only an efficiency concern (and you normally don't want to concern yourself with efficiency tuning while you're designing and assembling your program), there's more at stake: as you'll see in the remainder of the chapt
Although this may at first seem like only an efficiency concern (and you normally don't want to concern yourself with efficiency tuning while you're designing and assembling your program), there's more at stake: as you'll see in the remainder of the chapt
尽管初看起来，仅仅是一个与效率相关的难题（并且你在设计和装配程序时，一般不会想到通过调整效率来关心一下自己的程序），这更像是在赌博：本章余下的内容中你将会看到，通过传值方式需要给对象传递一个拷贝构造函数，但并不老是行得通。