e.next = nil // avoid memory leaks e.prev = nil // avoid memory leaks

/Go/src/container/list/list.go:10

// remove removes e from its list, decrements l.len, and returns e.
func (l *List) remove(e *Element) *Element {
   e.prev.next = e.next
   e.next.prev = e.prev
   e.next = nil // avoid memory leaks
   e.prev = nil // avoid memory leaks
   e.list = nil
   l.len--
   return e
}