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<?php var_dump( '{!' . (string)2 + 1 . '}' ); // The "." and "+" have the same precedence, so how operations are grouped // comes down to their associativity. Left associativity means the operations // were grouped like: var_dump( (('{!' . (string)2) + 1) . '}' );
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
string(4) "{!3}" Fatal error: Uncaught TypeError: Unsupported operand types: string + int in /in/i2HUO:8 Stack trace: #0 {main} thrown in /in/i2HUO on line 8
Process exited with code 255.
Output for 7.4.0 - 7.4.33
Deprecated: The behavior of unparenthesized expressions containing both '.' and '+'/'-' will change in PHP 8: '+'/'-' will take a higher precedence in /in/i2HUO on line 3 Warning: A non-numeric value encountered in /in/i2HUO on line 3 string(2) "1}" Warning: A non-numeric value encountered in /in/i2HUO on line 8 string(2) "1}"
Output for 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33
Warning: A non-numeric value encountered in /in/i2HUO on line 3 string(2) "1}" Warning: A non-numeric value encountered in /in/i2HUO on line 8 string(2) "1}"
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 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, 5.6.7 - 5.6.28, 7.0.0 - 7.0.20
string(2) "1}" string(2) "1}"

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