来自此代码模板，该模板可以：

{ 
  fn f3( _s : &String) {}

  fn f( s : &String) -> impl FnMut() {
   let s2 = s.clone();
   move || f3( &s2)
  }

  let mut f2 = f( &"123".to_string());

  f2();
}

如果我这样修改代码：

{ 
  fn f3( _s : &[u8]) {}

  fn f( s : &[u8]) -> impl FnMut() {
   // let s2 = s.clone(); // don't work
   let s2 = Vec::from(s);
   move || f3( &s2[..])
  }

  let mut f2 = f( &vec![1u8][..]);

  f2();
}

我不能使用'让s2 = s.克隆（）;'。这将显示错误消息：

1169 |   fn f( s : &[u8]) -> impl FnMut() {
     |                       ------------ this return type evaluates to the `'static` lifetime...
1170 |    let s2 = s.clone();
     |               ^^^^^ ...but this borrow...
     |
note: ...can't outlive the anonymous lifetime #1 defined on the function body at 1169:3

克隆如何启动借用？