Rust 学习 0

• 安装Rust 后，本地有文档： file:///usr/local/share/doc/rust/html/index.html file:///usr/local/share/doc/rust/html/rand/index.html
• Rust 每行末尾都需要分号“;”，有时挺繁琐的
• guessing_gname 中

extern crate rand;

let secret_number = rand::thread_rng().gen_range(1, 101);

但忘记 use rand::Rng;，编译失败：

Compiling guessing_gname v0.1.0 (file:///Users/Simon/WorkSpaces/Rust/guessing_gname)
src/main.rs:9:44: 9:68 error: type `rand::ThreadRng` does not implement any method in scope named `gen_range`
src/main.rs:9     let secret_number = rand::thread_rng().gen_range::<i32>(1, 101);
                                                         ^~~~~~~~~~~~~~~~~~~~~~~~
src/main.rs:9:44: 9:68 help: methods from traits can only be called if the trait is in scope; the following trait is implemented but not in scope, perhaps add a `use` for it:
src/main.rs:9:44: 9:68 help: candidate #1: use `rand::Rng`
error: aborting due to previous error
Could not compile `guessing_gname`.

To learn more, run the command again with --verbose.

代码中没有明确使用 rand::Rng，编译器应该自动推导才对，不该让程序员来主动导入。或使用工具自动导入。