export default Ember.Object.create
  # go from string:
  #   19,  21-27,   98-101
  # to
  #   [19,21,22,23,24,25,26,27,98,99,100,101]
  parse: (identifier) ->
    ids = []
    return ids unless identifier
    String(identifier).replace(/\s/g, '').split(',').forEach (id_spec) ->
      [id_start, id_end] = id_spec.split('-')
      id_start = parseInt(id_start)
      if id_end
        range_result = [id_start..id_end]
        ids = ids.concat range_result
      else
        ids.push id_start
    ids