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run code in 200+ php & hhvm versions
Bugs & Features
<?php class Student { private $classes; public function __construct($classes) { $this->classes = $classes; } public function getClasses() { return $this->classes; } public function combineClasses(Student $otherStudent) { $allClasses = array_unique(array_merge($this->classes, $otherStudent->classes)); $this->classes = $allClasses; $otherStudent->classes = $allClasses; } } $mary = new Student(['CompSci2001', 'CompSci2002']); $john = new Student(['CompSci2002', 'CompSci2003']); $mary->combineClasses($john); var_dump($mary->getClasses()); var_dump($john->getClasses());
based on 3nLfb
Output for 5.6.0 - 7.2.8
array(3) { [0]=> string(11) "CompSci2001" [1]=> string(11) "CompSci2002" [3]=> string(11) "CompSci2003" } array(3) { [0]=> string(11) "CompSci2001" [1]=> string(11) "CompSci2002" [3]=> string(11) "CompSci2003" }