note 130241 added to countable.count

From: Date: Wed, 09 Apr 2025 18:47:51 +0000
Subject: note 130241 added to countable.count
Groups: php.notes 
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First, the commonly referenced example of Countable is somewhat misleading from an OOP perspective, as it unintentionally violates some key principles. While it demonstrates the concept of Countable, it does so in a way that could cause confusion. According to the Countable interface: <?php /** * Count elements of an object * @link https://php.net/manual/en/countable.count.php * @return int<0,max> The custom count as an integer. * <p> * The return value is cast to an integer. * </p> */ #[TentativeType] public function count(): int; ?> This means that the count() method should not modify the state of an object—it should simply return an integer value, aligning with SOLID principles. A proper OOP approach would be: <?php class Counter implements Countable { private $count = 0; // Returns the item count of the object public function count(): int { return $this->count; } public function increment(): void { $this->count++; } } $counter = new Counter; for ($i = 0; $i < 10; ++$i) { $counter->increment(); echo "I have been incremented " . count($counter) . " times\n"; } ?> Here, count() correctly returns the number of elements, while increment() is responsible for modifying the state of the object. A separate discussion can be had about whether to use count($object) or $object->count(), but that’s a different topic. ---- Server IP: 45.112.84.4 Probable Submitter: 80.90.5.137 (proxied: 79.194.221.163) ---- Manual Page -- https://php.net/manual/en/countable.count.php Edit -- https://main.php.net/note/edit/130241 Del: integrated -- https://main.php.net/note/delete/130241/integrated Del: useless -- https://main.php.net/note/delete/130241/useless Del: bad code -- https://main.php.net/note/delete/130241/bad+code Del: spam -- https://main.php.net/note/delete/130241/spam Del: non-english -- https://main.php.net/note/delete/130241/non-english Del: in docs -- https://main.php.net/note/delete/130241/in+docs Del: other reasons-- https://main.php.net/note/delete/130241 Reject -- https://main.php.net/note/reject/130241 Search -- https://main.php.net/manage/user-notes.php

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