func(Polish,{
  sub({
    let(op,unvector(left([x],1))):
    let(dat,right([x],len([x])-2)):
    let(nfx,
      stack(mid([x],2,1),
        apply([op],[dat]))
    ):
    print_reduce(join,[nfx])
  })
}):

print_`polish.txt',: