for( -1 .. 1) {
 print s2u($_), "\n";
}

sub s2u {
Dump sprintf("%u", $_[0]) + 0;
}

=head1 output

SV = IV(0x732998) at 0x73299c
  REFCNT = 1
  FLAGS = (PADTMP,IOK,pIOK,IsUV)
  UV = 4294967295

SV = IV(0x732998) at 0x73299c
  REFCNT = 1
  FLAGS = (PADTMP,IOK,pIOK)
  IV = 0

SV = IV(0x732998) at 0x73299c
  REFCNT = 1
  FLAGS = (PADTMP,IOK,pIOK)
  IV = 1

=cut