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run code in 300+ PHP versions simultaneously
<?php class Dictionary implements ArrayAccess { function offsetExists($offset) {} function offsetGet($offset) {} function offsetUnset($offset) {} function offsetSet($offset, $value) { if (!is_string($offset)) { throw new InvalidArgumentException(); } } } try { $Dictionary = new Dictionary(); $Dictionary["12"] = 0xDEADBEEF; echo "No Exception for \"12\"\n"; } catch (InvalidArgumentException $e) { echo "Caught Exception for \"12\"\n"; } try { $str = "12"; $Dictionary[$str] = 0xDEADBEEF; echo "No Exception for \$variable = \"12\"\n"; } catch (InvalidArgumentException $e) { echo "Caught Exception for \$variable = \"12\"\n"; } ?>
based on d4mJW
Output for 7.3.0 - 7.3.28, 7.4.0 - 7.4.16, 8.0.0 - 8.0.3
No Exception for "12" No Exception for $variable = "12"
Output for 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
Caught Exception for "12" No Exception for $variable = "12"