/**
* @return Group
*/
public function even()
{
$group = Group::create();
foreach ($this->toArray() as $index => $item) {
if (!($index & 1)) {
$group->append($item);
}
}
return $group;
}
/**
* @param string $name
* @return Group
*/
public function getGroup($name)
{
if (isset($this->groups[$name])) {
return $this->groups[$name];
}
return $this->groups[$name] = Group::createWithName($name);
}
