       r != ref 
     end)
   end
+
+  @doc """
+  Map `{pid, id}` tuples to id only
+  """
+  def ids(tuples) do
+    Enum.map(tuples, fn({_p,id}) -> id end)
+  end
 end
 


  ## Example:
      iex> roots = ApmIssues.Repository.root_issues()
      iex> Enum.map(roots, fn({_p,i}) -> i end)
      ["Item-2", "Item-1"]
  """
  def root_issues() do

      iex> ApmIssues.Repository.drop!
      iex> ApmIssues.Repository.seed()
      iex> all = ApmIssues.Repository.all()
      iex> ApmIssues.Repository.ids(all)
      ["Item-2.2", "Item-2.1", "Item-2", "Item-1"]
  """
  def all() do
