Python“移动语义”

Question

我有一个主线程，需要定期将缓冲区刷新到磁盘，因此每次我创建一个新线程来运行 json.dump(buffer) 时。但在此之后我需要立即清除缓冲区，那么 Python 中是否有“移动语义”让我无需对其进行深层复制即可执行此操作？

Answer 1

也许使用包装类来帮助移动。

class ExpensiveObj: pass

class ExpensiveObjHolder:
  def __init__(self, obj: ExpensiveObj):
    self._obj = obj
  def move(self) -> ExpensiveObj:
    obj, self._obj = self._obj, None
    if not obj:
      raise UseAfterMoveError
    return obj

def consume_obj(obj: ExpensiveObj):
  info = ParseObj(obj)
  del obj
  some_time_consuming_task(info)

holder = ExpensiveObjHolder(ExpensiveObj())
consume_obj(holder.move())  # passing ownership, ref of obj in holder released.