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<?php function filterKeys($array,$search){ $allowed=array_filter(array_keys($array),function($key){return stristr($key,$search);}); return array_intersect_key($array,array_flip($allowed)); } var_dump(filterKeys(array('foo'=>'bar', 'moo'=>'baz'),'foo')); ?>
Output for 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
Warning: Undefined variable $search in /in/LZaBL on line 3 Deprecated: stristr(): Passing null to parameter #2 ($needle) of type string is deprecated in /in/LZaBL on line 3 Warning: Undefined variable $search in /in/LZaBL on line 3 Deprecated: stristr(): Passing null to parameter #2 ($needle) of type string is deprecated in /in/LZaBL on line 3 array(2) { ["foo"]=> string(3) "bar" ["moo"]=> string(3) "baz" }
Output for 8.0.0 - 8.0.30
Warning: Undefined variable $search in /in/LZaBL on line 3 Warning: Undefined variable $search in /in/LZaBL on line 3 array(2) { ["foo"]=> string(3) "bar" ["moo"]=> string(3) "baz" }
Output for 7.3.12 - 7.3.31, 7.4.0 - 7.4.33
Notice: Undefined variable: search in /in/LZaBL on line 3 Deprecated: stristr(): Non-string needles will be interpreted as strings in the future. Use an explicit chr() call to preserve the current behavior in /in/LZaBL on line 3 Notice: Undefined variable: search in /in/LZaBL on line 3 Deprecated: stristr(): Non-string needles will be interpreted as strings in the future. Use an explicit chr() call to preserve the current behavior in /in/LZaBL on line 3 array(0) { }
Output for 7.3.32 - 7.3.33
array(0) { }
Output for 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 - 7.1.10, 7.2.0 - 7.2.33
Notice: Undefined variable: search in /in/LZaBL on line 3 Notice: Undefined variable: search in /in/LZaBL on line 3 array(0) { }
Output for 4.4.2 - 4.4.9, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17
Parse error: syntax error, unexpected T_FUNCTION in /in/LZaBL on line 3
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1, 5.0.0 - 5.0.5
Parse error: parse error, unexpected T_FUNCTION in /in/LZaBL on line 3
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error in /in/LZaBL on line 3
Process exited with code 255.

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