src/precore/util/Iterators.php
public static function filterBy(Iterator $unfiltered, string $className) : Iterator
    {
        return self::filter($unfiltered, Predicates::instance($className));
    }
public static function filterBy(Iterator $unfiltered, string $className) : Iterator
    {
        return self::filter($unfiltered, Predicates::instance($className));
    }
public static function filterBy ( Iterator $ unfiltered , string $ className ) : Iterator { return self :: filter ( $ unfiltered , Predicates :: instance ( $ className ) ) ; }
Returns all instances of class type in unfiltered.
The returned iterator has elements whose class is type or a subclass of type.

@param Iterator $unfiltered
@param string $className
@return Iterator
Returns all instances of class type in unfiltered . The returned iterator has elements whose class is type or a subclass of type .