record of interesting ruby one-liners while I study Ruby on the way

Ruby_One_Liners.rb

# source code from internet & Why's (Poignant) Guide to Ruby

# fibonacci by ruby one liners
fibonacci = Hash.new { |h, k| x < 2 ? k : h[k] = h[k-1] + h[k-2] }

# print something several times
5.times { print "Odelay!" }

# unless
exit unless "restaurant".include? "aura"
# small trick, do it only when a is true and b is not true
print "We're using plastic 'cause we don't have glass." if plastic_cup unless glass_cup


# print array
['toast', 'cheese', 'wine'].each { |food| print food.capitalize  }

# one line to determine if a number is a prime
# http://www.noulakaz.net/weblog/2007/03/18/a-regular-expression-to-check-for-prime-numbers/
def is_prime(n)
  ("1" * n) !~ /^1?$|^(11+?)\1+$/
end