base:=Dictionary(
   "name", 	"Rocket Skates",
   "price", 	12.75,
   "color", 	"yellow",);
update:=Dictionary(
   "price", 	15.25,
   "color", 	"red",
   "year", 	1974,);

update.pump( new:=base.copy() );

new.pump(Void,fcn([(k,v)]){ println("%s\t%s".fmt(k,v)) });