pub fn new() -> Weak<T, A> {
        Weak {
            ptr: Ptr::dangling(),
        }
    }
/// Creates a new dangling weak pointer
Creates a new dangling weak pointer
Creates a new dangling weak pointer
pub fn new() -> Weak<T, A> {
        Weak {
            ptr: Ptr::dangling(),
        }
    }
pub fn new ( ) -> Weak < T , A > { Weak { ptr : Ptr :: dangling ( ) , } }
Creates a new dangling weak pointer
Creates a new dangling weak pointer