RosettaCodeData/Task/First-class-environments/Zkl/first-class-environments-2.zkl

var es=(1).pump(12,List,Env);
while(1){
   ns:=es.run(True);
   ns.pump(String,"%4d".fmt).println();
   if (not ns.filter('!=(1))) break;
}
println("Counts:");
es.pump(String,fcn(e){"%4d".fmt(e.container.cnt)}).println();