delete [JavaScript snippet]

function main() {

  var o = {seek   : "find",
           knock  : "open",
           listen : "hear",
           ask    : "give",
           now    : "then" ,
          }

  txt_out (o.listen); // hear
  txt_out (o.now   ); // then

  txt_out('----');

  delete o.listen;
  delete o["now"];

  txt_out (o.listen); // undefined
  txt_out (o.now);    // undefined
}