.expect("Index entered was not a number"); let element = a[index]; println!("The value of the element at index {index} is: {element}"); } 此代码编译成功。如果您使用 cargo run 运行此代码并输入 0、1、2、3 或 4，程序将在数组 为这是一个表达式，我们想要返回它的值。 让我们看看另一个例子： 文件名：src/main.rs fn main() { let x = plus_one(5); println!("The value of x is: {x}"); } fn plus_one(x: i32) -> i32 { x + 1 } 运行代码会打印出 The value of x is: 6。但如果在包含 表达式变成语句，我们将看到一个错误。 文件名：src/main.rs fn main() { let x = plus_one(5); 55/562Rust 程序设计语言 简体中文版 println!("The value of x is: {x}"); } fn plus_one(x: i32) -> i32 { x + 1; } 运行代码会产生一个错误，如下： $ cargo

attribute. The style inspector displays the CSS styles associated with the selected element. The entries here come from the element's style attribute, from matching stylesheet rules, or inherited from other elements contains more helpful tools: Layout contains information about the box model properties of the element. Note that flex and grid do not work yet. Computed, which contains all the CSS computed values after #parsing-main-incdata:perform-a-microtask-checkpoint. Again in the parser, ss part of creating an element. This corresponds to #creating-and- inserting-nodes:perform-a-microtask-checkpoint. As part of cleaning-up