2. This syntax only applies to objects/classes, not built-in types. 该语法仅仅用于类和对象,没有内置于类型中。
3. Each type, whether a built-in or class type, defines the meaning of a (possibly empty) set of operations on objects of that type. 每种类型,无论是内置类型还是类类型,都对该类型对象的一组(可能为空的)操作的含义进行了定义。
英英解释
adj.
1. existing as an essential constituent or characteristic