magic-self.edh

{

  class DynAttrs {

    method __init__ (** attrs ) {
      this._d = dict(** attrs )
      this._n = 111
    }


    method (@) ( attrKey ) this._d[ attrKey ]

    method (@=) ( attrKey, *optionalVal ) case optionalVal of {
      { () } -> this._d[ attrKey ] = nil
      { ( attrVal ) } -> this._d[ attrKey ] = attrVal
      _ -> assert( false, 'impossible' )
    }


    property$
    method n () this._n

    setter$
    method n (* optionalVal ) case optionalVal of {
      { () } -> this._n = nil
      { ( val ) } -> this._n = val
      _ -> assert( false, 'impossible' )
    }

  }

}

dao = DynAttrs( a=3, b=2, c=5 )
dao._d

dao.a
dao.a=7
dao.a
dao._d

dao.b=nil
dao._d
dao.b # this should throw

dao.n
dao.n=333
dao.n
dao._d
dao.n=nil
dao.n # this should throw