Question

I have some array

>> a = ["a..c", "0..2"]
=> ["a..c", "0..2"]

I need convert this array to another array

>> b = ("a".."c").to_a + (0..2).to_a
=> ["a", "b", "c", 0, 1, 2]

How I can do it?

Answer 1

what about this?

a = ["a..c", "0..2"]

b = a.map { |e| Range.new( *(e).split('..') ).to_a }.flatten

no flat_map used so it works the same on all versions

as @steenslag correctly mentioned, this version does not convert to integers.

here is a version that does:

b = a.map do |e| 
  Range.new( *(e).split('..').map{ |c| c =~ /\A\d+\Z/ ? c.to_i : c } ).to_a 
end.flatten

see it in action here