# 起步-helloworld

创建目录

```
mkdir hello_world
cd hello_world
```

创建main.rs

```rust
//第二，println! 调用了一个 Rust 宏（macro）。如果是调用函数，则应输入 println（没有!）
fn main() {
    println!("Hello, world!");
}
```

编译

```
$ rustc main.rs
$ ./main
Hello, world!
```

目录会多出编译文件（在 Windows 上，输入命令 `.\main.exe`，而不是 `./main`：）

![](/files/-LokoUfT8kBoEokAES8e)


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