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<?php // Mock of your Exchange class - you did not post the structure so its fairly basic. class Exchange { /** * @var string */ private $fooVar = 'foo'; public function foo(): string { return 'foo'; } } class YourExchange extends Exchange { public function bar(): string { return $this->foo(); } } var_dump((new YourExchange())->bar());
Output for 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
string(3) "foo"
Output for 5.6.0 - 5.6.40
Parse error: syntax error, unexpected ':', expecting ';' or '{' in /in/ETi27 on line 10
Process exited with code 255.
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