gistfile1.rb

require 'pp'

class Object
  def tap
    yield self
    self
  end
  def tapp
    pp self
    self
  end
end

a = [nil, :apple, [:others]].flatten.tapp.compact.tapp
#> [nil, :apple, :others]
#> [:apple, :others]

a.tapp
#> [:apple, :others]