Understanding Ownership
NOTE:
一、rust在语言层使用了ownership概念，它是rust的核心特性；相比之下，C++的ownership，并没有出现在语言层，相比之下，弱了很多
Ownership is Rust’s most unique feature, and it enables Rust to make memory safety guarantees without needing a garbage collector. Therefore, it’s important to understand how ownership works in Rust. In this chapter, we’ll talk about ownership as well as several related features: borrowing, slices, and how Rust lays data out in memory.
What Is Ownership?
Rust’s central feature is ownership. Although the feature is straightforward to explain, it has deep implications for the rest of the language.
All programs have to manage the way they use a computer’s memory while running. Some languages have garbage collection that constantly looks for no longer used memory as the program runs; in other languages, the programmer must explicitly allocate and free the memory. Rust uses a third approach: memory is managed through a system of ownership with a set of rules that the compiler checks at compile time. None of the ownership features slow down your program while it’s running.
NOTE:
一、rust的ownership是可以在compile time进行check的，也就是说，是static的