# File lib/ruote/exp/fe_concurrence.rb, line 411
    def apply_children

      # a) register children
      # b) persist
      # c) trigger children applies

      msgs = []

      tree_children.each_with_index do |c, i|
        msgs << pre_apply_child(i, h.applied_workitem.dup, false)
      end

      persist_or_raise

      msgs.each { |m| @context.storage.put_msg('apply', m) }
    end