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<?php class Foo { public readonly int $bar; public function set(int $i) { $this->bar = &$i; } } $i = 1; $foo = new Foo(); $foo->set($i); $i = 20; var_dump($foo->bar);
Output for 8.1.0 - 8.1.8
int(1)
Output for 7.4.0 - 7.4.33
Parse error: syntax error, unexpected 'int' (T_STRING), expecting variable (T_VARIABLE) in /in/NMDAp on line 6
Process exited with code 255.
Output for 8.0.1 - 8.0.30
Parse error: syntax error, unexpected identifier "int", expecting variable in /in/NMDAp on line 6
Process exited with code 255.
Output for 8.1.9 - 8.1.34, 8.2.0 - 8.2.34, 8.3.0 - 8.3.35, 8.4.1 - 8.4.26, 8.5.0 - 8.5.11
Fatal error: Uncaught Error: Cannot indirectly modify readonly property Foo::$bar in /in/NMDAp:10 Stack trace: #0 /in/NMDAp(17): Foo->set(1) #1 {main} thrown in /in/NMDAp on line 10
Process exited with code 255.

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