参考资料

1. 《Programming -- Principles and Practice Using C++ (3rd Edition)》—— Bjarne Stroustrup

C++ 基础定义

The notion of type is central to C++ and most other programming languages. Let’s take a closer and slightly more technical look at types:

• A type defines a set of possible values and a set of operations (for an object).
• An object is some memory that holds a value of a given type.
• A value is a set of bits in memory interpreted according to a type.
• A variable is a named object.
• A declaration is a statement that gives a name and a type to an object.
• A definition is a declaration that sets aside memory for an object.

Informally, we think of an object as a box into which we can put values of a given type. An int box can hold integers, such as 7, 42, and -399.