How do I modify an array while I am iterating over it in Ruby?

user_215895 0
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I'm just learning Ruby so apologies if this is too newbie for around here, but I can't work this out from the pickaxe book (probably just not reading carefully enough). Anyway, if I have an array like so:

arr = [1,2,3,4,5]

...and I want to, say, multiply each value in the array by 3, I have worked out that doing the following:

arr.each {|item| item *= 3}

...will not get me what I want (and I understand why, I'm not modifying the array itself).

What I don't get is how to modify the original array from inside the code block after the iterator. I'm sure this is very easy.

iteration ruby arrays
4 Answers

Others have already mentioned that array.map is the more elegant solution here, but you can simply add a "!" to the end of array.each and you can still modify the array. Adding "!" to the end of #map, #each, #collect, etc. will modify the existing array.

user_162090090
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