! $layouts = al az br cn us

! layout        option          =       symbols
  $layouts      some:opt        =       +extra

! layout[1]     option          =       symbols
  $layouts      some:opt        =       +extra:1

! layout[2]     option          =       symbols
  $layouts      some:opt        =       +extra:2

! layout[3]     option          =       symbols
  $layouts      some:opt        =       +extra:3

! layout[4]     option          =       symbols
  $layouts      some:opt        =       +extra:4

! model         = symbols
  *             = default_symbols

! model         = keycodes
  *             = default_keycodes

! model         = types
  *             = default_types

! model         = compat
  *             = default_compat