sub is_blessed {
      return (ref $_[0]
              && ! grep    { ref $_[0] eq $_ }
                   qw[ SCALAR ARRAY HASH  CODE GLOB LVALUE ]
                )  ? 1 : 0;
  }

# Hope nobody defines a sub by this name
sub UNIVERSAL::a_sub_not_likely_to_be_here { ref($_[0]) }

sub blessed ($) {
  local($@, $SIG{}, $SIG{});
  length(ref($_[0]))
    ? eval { $_[0]->a_sub_not_likely_to_be_here }
    : undef
}