Return a (temporarily) invisible copy of an object.
返回一个对象(临时)无形的副本。
用法----------Usage----------
参数----------Arguments----------
参数:x
an arbitrary R object.
任意一个R对象。
Details
详情----------Details----------
This function can be useful when it is desired to have functions return values which can be assigned, but which do not print when they are not assigned.
当它需要有函数的返回值可以分配,这个功能是有用的,但不打印时,他们没有分配。