# File lib/backports/1.8.7/array.rb, line 168 def sample(n = Backports::Undefined) return self[Kernel.rand(size)] if n == Backports::Undefined n = Backports.coerce_to_int(n) raise ArgumentError, "negative array size" if n < 0 n = size if n > size result = Array.new(self) n.times do |i| r = i + Kernel.rand(size - i) result[i], result[r] = result[r], result[i] end result[n..size] = [] result end