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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.

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1 Answer

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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.


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