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ruby oneliner vs groovy

i was going through railstutorial and saw the following one liner

('a'..'z').to_a.shuffle[0..7].join

it creates random 7 character domain name like following:

 hwpcbmze.heroku.com
 seyjhflo.heroku.com
 jhyicevg.heroku.com

I tried converting the one liner to groovy but i could only come up with:

def range = ('a'..'z')
def tempList = new ArrayList (range)
Collections.shuffle(tempList)
println tempList[0..7].join()+".heroku.com"

Can the above be improved and made to a one liner? I tried to make the above code shorter by

println Collections.shuffle(new ArrayList ( ('a'..'z') ))[0..7].join()+".heroku.com"

However, apparently Collections.shuffle(new ArrayList ( ('a'..'z') )) is a null

Solution

  • Not having shuffle built-in adds the most to the length, but here's a one liner that'll do it:

    ('a'..'z').toList().sort{new Random().nextInt()}[1..7].join()+".heroku.com"

    Yours doesn't work because Collections.shuffle does an inplace shuffle but doesn't return anything. To use that as a one liner, you'd need to do this:

    ('a'..'z').toList().with{Collections.shuffle(it); it[1..7].join()+".heroku.com"}