add element to ruby array return new array

ruby arrays copy new-operator
srchulo picture srchulo · Jan 31, 2012 · Viewed 18.2k times · Source

I would like to add an element to an array but without actually changing that array and instead it returning a new one. In other words, I want to avoid:

arr = [1,2]
arr << 3

Which would return:

[1,2,3]

Changing arr itself. How can I avoid this and create a new array?

Answer

Sergio Tulentsev picture Sergio Tulentsev · Jan 31, 2012

You can easily add two arrays in Ruby with plus operator. So, just make an array out of your element.

arr = [1, 2]
puts arr + [3]
# => [1, 2, 3]
puts arr
# => [1, 2]

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