= || println!("From closure: {list:?}"); println!("Before calling closure: {list:?}"); only_borrows(); println!("After calling closure: {list:?}"); } 示例 13-4：定义并调用一个捕获不可变引用的闭包 这个示例也展示了变量 `target/debug/closure-example` Before defining closure: [1, 2, 3] Before calling closure: [1, 2, 3] From closure: [1, 2, 3] After calling closure: [1, 2, 3] 接下来在示例 13-5 中，我们修改闭包体让它向 list vector 增加一个元素。闭包现在捕获一 }"); let mut borrows_mutably = || list.push(7); borrows_mutably(); println!("After calling closure: {list:?}"); } 示例 13-5：定义并调用一个捕获可变引用的闭包 代码可以编译、运行并打印： $ cargo run Compiling closure-example