/**
* {@inheritDoc}
*/
public function groupBy(callable $groupKeyFunction)
{
$groupedMap = new self();
foreach ($this->keyIdentityPositionMap as $identityHash => $position) {
$keyCopy = $key = $this->keys[$position];
$valueCopy = $value =& $this->values[$position];
$groupKey = $groupKeyFunction($valueCopy, $keyCopy);
if ($groupedMap->contains($groupKey)) {
$groupMap = $groupedMap->get($groupKey);
} else {
$groupMap = new self();
$groupedMap->set($groupKey, $groupMap);
}
$groupMap->setInternal($key, $value, $identityHash, true);
}
return $groupedMap;
}
/**
* Create a new collection from an array, validate the keys, and add default values where missing
*
* @param array $config Configuration values to apply.
* @param array $defaults Default parameters
* @param array $required Required parameter names
*
* @return self
* @throws InvalidArgumentException if a parameter is missing
*/
public static function fromConfig(array $config = null, array $defaults = null, array $required = null)
{
$collection = new self($defaults);
foreach ((array) $config as $key => $value) {
$collection->add($key, $value);
}
foreach ((array) $required as $key) {
if ($collection->contains($key) === false) {
throw new InvalidArgumentException("Config must contain a '{$key}' key");
}
}
return $collection;
}
/**
* Get all the unique values in the collection.
*
* @param bool $preserveKeys
*
* @return CollectionInterface
*/
public function unique($preserveKeys = true)
{
$values = new self();
$this->each(function ($item) use($values, $preserveKeys) {
if (!$values->contains($item)) {
if ($preserveKeys) {
}
$values->push($item);
}
});
return $values;
}
/**
* {@inheritdoc}
*/
public function groupBy(callable $discriminator) : MapInterface
{
if ($this->size() === 0) {
throw new GroupEmptyMapException();
}
$map = null;
foreach ($this->pairs as $pair) {
$key = $discriminator($pair->key(), $pair->value());
if ($map === null) {
$type = gettype($key);
$map = new self($type === 'object' ? get_class($key) : $type, SequenceInterface::class);
}
if ($map->contains($key)) {
$map = $map->put($key, $map->get($key)->add($pair));
} else {
$map = $map->put($key, new Sequence($pair));
}
}
return $map;
}
