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<?php $var = "xyz\n"; $obj = new stdClass(); $obj->var = "abc\n"; $key = 'var'; echo $$key; // Works echo ${$key}; // Works // echo {$$key}; E_ERROR echo "$$key"; // Does not work? Outputs "$var" echo "${$key}"; // Works echo "{$$key}"; // Works echo $obj->var; // Works echo $obj->{$key}; // Works // echo $obj->${key}; E_ERROR echo $obj->$$key; // E_NOTICE Undefined property echo $obj->${$key}; // E_NOTICE Undefined property echo $obj->{$$key}; // E_NOTICE Undefined property echo "$obj->var"; // Works // echo "${obj->var}"; // Syntax error echo "{$obj->var}"; // Works // echo "$obj->$$key"; // Catchable fatal error // echo "$obj->${$key}"; // Catchable fatal error // echo "$obj->{$$key}"; // Catchable fatal error // echo "${obj->$$key}"; // Syntax error // echo "${obj->${$key}}"; // Syntax error // echo "${obj->{$$key}}"; // Syntax error
Output for 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
Deprecated: Using ${expr} (variable variables) in strings is deprecated, use {${expr}} instead in /in/dpbES on line 12 xyz xyz $varxyz xyz abc abc Warning: Undefined property: stdClass::$xyz in /in/dpbES on line 19 Warning: Undefined property: stdClass::$xyz in /in/dpbES on line 20 Warning: Undefined property: stdClass::$xyz in /in/dpbES on line 21 abc abc
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.33
xyz xyz $varxyz xyz abc abc Warning: Undefined property: stdClass::$xyz in /in/dpbES on line 19 Warning: Undefined property: stdClass::$xyz in /in/dpbES on line 20 Warning: Undefined property: stdClass::$xyz in /in/dpbES on line 21 abc abc
Output for 5.2.6 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.31, 7.4.0 - 7.4.33
xyz xyz $varxyz xyz abc abc Notice: Undefined property: stdClass::$xyz in /in/dpbES on line 19 Notice: Undefined property: stdClass::$xyz in /in/dpbES on line 20 Notice: Undefined property: stdClass::$xyz in /in/dpbES on line 21 abc abc
Output for 7.3.32 - 7.3.33
xyz xyz $varxyz xyz abc abc abc abc
Output for 5.0.0 - 5.0.5, 5.1.1 - 5.1.6, 5.2.0 - 5.2.5
xyz xyz $varxyz xyz abc abc Notice: Undefined property: stdClass::$xyz in /in/dpbES on line 19 Notice: Undefined property: stdClass::$xyz in /in/dpbES on line 20 Notice: Undefined property: stdClass::$xyz in /in/dpbES on line 21 abc abc
Output for 5.1.0
Fatal error: fatal flex scanner internal error--end of buffer missed in /in/dpbES on line 34
Process exited with code 255.
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9
xyz xyz $varxyz xyz abc abc Notice: Undefined property: xyz in /in/dpbES on line 19 Notice: Undefined property: xyz in /in/dpbES on line 20 Notice: Undefined property: xyz in /in/dpbES on line 21 abc abc
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47.5 ms | 415 KiB | 5 Q