impl<'a, T: 'a + fmt::Debug> fmt::Debug for SymmetricDifference<'a, T> {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
f.debug_tuple("SymmetricDifference")
impl<'a, T: 'a + fmt::Debug> fmt::Debug for SymmetricDifference<'a, T> {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
f.debug_tuple("SymmetricDifference")