Small correction:

ae = 'a'..'e'

ccae = ['<', *r, '>'] # => ['<', 'a', 'b', 'c', 'd', 'e', '>']

I'm guessing *r in the second line should have been *ae (or ae in the first line should have been named r)

Also

"It is new possible" should prpbably have been "It is now possible"