How to chunk an array in Ruby

Question

In Ruby 1.8.6, I have an array of, say, 100,000 user ids, each of which is an int. I want to perform a block of code on these user ids but I want to do it in chunks. For e

Answer 1

Rails has in_groups_of, which under the hood uses each_slice.

userids.in_groups_of(100){|group|
  //process group
}

Answer 2

Use each_slice:

require 'enumerator'
userids.each_slice(100) do |a|
  # do something with a
end