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<?php $var; echo 'before: '; var_dump($var); useRefs($var); echo 'after: '; var_dump($var); useRefs($var); echo 'last: '; var_dump($var); function useRefs(&$var) { if ($var === null) { $var = 'test'; } else { $var = null; } }
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.19, 8.3.0 - 8.3.7
before: Warning: Undefined variable $var in /in/8etck on line 4 NULL after: string(4) "test" last: NULL
Output for 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.31, 7.4.0 - 7.4.33
before: Notice: Undefined variable: var in /in/8etck on line 4 NULL after: string(4) "test" last: NULL
Output for 7.3.32 - 7.3.33
before: NULL after: string(4) "test" last: NULL
Output for 5.0.4 - 5.0.5
Notice: Undefined variable: var in /in/8etck on line 3 before: Notice: Undefined variable: var in /in/8etck on line 4 NULL after: string(4) "test" last: NULL
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.3
Notice: Undefined variable: var in /in/8etck on line 3 before: Notice: Undefined variable: var in /in/8etck on line 4 NULL after: string(4) "test" last: NULL
preferences:
225.31 ms | 402 KiB | 341 Q