Function clone_body_fn
fn clone_body_fn<F, B>(f: F) -> CloneBodyFn<F>
where
F: Fn(&B) -> Option<B>
Create a new redirection Policy from a closure F: Fn(&B) -> Option<B>.
[clone_body][Policy::clone_body] method of the returned Policy delegates to the wrapped
closure and [redirect][Policy::redirect] method always returns Action::Follow.