# File lib/ruote/exp/flowexpression.rb, line 506
    def handle_on_error (msg, error)

      return false if h.state == 'failing'

      oe_parent = lookup_on_error

      return false unless oe_parent
        # no parent with on_error attribute found

      handler = oe_parent.on_error.to_s

      return false if handler == ''
        # empty on_error handler nullifies ancestor's on_error

      workitem = msg['workitem']

      workitem['fields']['__error__'] = [
        h.fei, Ruote.now_to_utc_s, error.class.to_s, error.message, error.backtrace ]

      @context.storage.put_msg(
        'fail',
        'fei' => oe_parent.h.fei,
        'workitem' => workitem)

      true # yes, error is being handled.
    end