Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

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

ruby - Change value of array element which is being referenced in a .each loop?

How do I get the following to happen: I want to change the value of an array element which is being referenced between pipe characters in a .each loop.

Here is an example of what I want to do, but is not currently working:

x = %w(hello there world)
x.each { |element|
   if(element == "hello") {
       element = "hi" # change "hello" to "hi"
   }
}
puts x # output: [hi there world]

It's hard to look up something so general.

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 Answer

0 votes
by (71.8m points)

You can get the result you want using collect! or map! to modify the array in-place:

x = %w(hello there world)
x.collect! { |element|
  (element == "hello") ? "hi" : element
}
puts x

At each iteration, the element is replaced into the array by the value returned by the block.


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 OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...