Question

I’m using an .each loop to iterate over an array. I want to change elements in this array, so I tried something like this:

ex = ["el01", "el02", "el03", "el04"]
ex.each do |el|
    if (el == "el02")
        el = "changed"
    end
end
puts ex

but it seems don’t works! It puts me :

el01
el02
el03
el04

I want to know what I did wrong! or if it can’t be done this way, how to do it.

Answer 1

You should use each:

ex = ["el01", "el02", "el03", "el04"]
ex.each do |str|
  # do with str, e.g., printing each element:
  puts str
end

Using for in Ruby is not recommended, as it simply calls each and it does not introduce a new scope.

However, if your intent is to change each element in the array, you should use map:

ex = ["el01", "el02", "el03", "el04"]
ex.map do |str|
  str.upcase
end
#=> ["EL01", "EL02", "EL03", "EL04"]