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
363 views
in Technique[技术] by (71.8m points)

duck typing - Ruby class types and case statements

What is the difference between

case item.class
when MyClass
  # do something here
when Array
  # do something different here
when String
  # do a third thing
end

and

case item.class
when MyClass.class
  # do something here
when Array.class
  # do something different here
when String.class
  # do a third thing
end

For some reason, the first one of these works sometimes and the second doesn't, and other times, the second one works and the first one doesn't. Why? Which one is the "proper" way to do it?

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)

You must use:

case item
when MyClass
...

I had the same problem: How to catch Errno::ECONNRESET class in "case when"?


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

1.4m articles

1.4m replys

5 comments

56.9k users

...