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<?php class a implements \Iterator, \Countable { private $a; private $b; private $c; private $keys = [ 'a', 'b', 'c' ]; private $pointer; public function __construc($a = null, $b = null, $c = null) { $this->a = $a; $this->b = $b; $this->c = $c; } public function count() { $pointer = 0; foreach ($this as $element) { if ($element) { $pointer++; } } return $pointer; } public function current() { $key = $this->key(); return $this->{$key}; } public function key() { $this->keys[$this->pointer]; } public function next() { $this->pointer++; } public function valid() { if (count($this->keys) < $this->pointer) { true; } return false; } public function rewind() { $this->pointer = 0; } } $me = new a('a'); var_dump($me->count()); foreach ($me as $key => $el) { var_dump($key, $el); }
Output for 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Deprecated: Return type of a::current() should either be compatible with Iterator::current(): mixed, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /in/7Sh9N on line 37 Deprecated: Return type of a::next() should either be compatible with Iterator::next(): void, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /in/7Sh9N on line 49 Deprecated: Return type of a::key() should either be compatible with Iterator::key(): mixed, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /in/7Sh9N on line 44 Deprecated: Return type of a::valid() should either be compatible with Iterator::valid(): bool, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /in/7Sh9N on line 54 Deprecated: Return type of a::rewind() should either be compatible with Iterator::rewind(): void, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /in/7Sh9N on line 63 Deprecated: Return type of a::count() should either be compatible with Countable::count(): int, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice in /in/7Sh9N on line 24 int(0)
Output for 5.4.1 - 5.4.45, 5.5.24 - 5.5.35, 5.6.7 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.10, 7.2.0 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30
int(0)
preferences:
199.63 ms | 404 KiB | 226 Q