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<?php interface Counter { /** @return self */ public function count(); /** @return int */ public function getCount(); } class EchoingCounter implements Counter { private $counter; public function __construct(Counter $counter) { $this->counter = $counter; } public function count() { echo __METHOD__ . "\n"; return $this->counter->count(); } public function getCount() { echo __METHOD__ . "\n"; return $this->counter->getCount(); } } class FluentCounter implements Counter { private $count = 0; public function count() { $this->count += 1; return $this; } public function getCount() { return $this->count; } } $counter = new EchoingCounter(new FluentCounter()); $counter = $counter->count()->count()->count()->count(); echo $counter->getCount();
Output for 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.30, 8.2.0 - 8.2.25, 8.3.0 - 8.3.13
EchoingCounter::count 4

preferences:
45.06 ms | 408 KiB | 5 Q