Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
413 views
in Technique[技术] by (71.8m points)

properties - python: are property fields being cached automatically?

My question is are the following two pieces of code run the same by the interpreter:

class A(object):
  def __init__(self):
     self.__x = None

  @property
  def x(self):
     if not self.__x:
        self.__x = ... #some complicated action
     return self.__x

and the much simpler:

class A(object):
  @property
  def x(self):
      return ... #some complicated action

I.e., is the interpreter smart enough to cache the property x?

My assumption is that x does not change - finding it is hard, but once you find it once there is no reason to find it again.

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

No, the getter will be called every time you access the property.


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...