PHP Magic Tricks

As a part of our joint #xmasmeetup we played a game called PHP Magic Tricks. Solutions were submitted on github.com/chr-hertel/php-magic-tricks.

Transcript

1. PHP Magic Tricks
   Symfony User Group Berlin
   

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2. DISCLAIMER
   

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3. TRY THIS
   AT HOME
   

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4. DON‘T DO THIS
   TO YOUR PROJECT
   

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5. Trick #1
   Twisted truth
   

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6. // Insert Magic Code Here
   var_dump(true === false);
   Code
   bool(true)
   Output
   Trick #1
   Twisted truth
   

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7. Trick #2
   Sum Sum Sum
   

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8. // Insert Magic Code Here
   var_dump(count($array), array_sum($array));
   $array[0] = 1;
   $array[1] = 2;
   $array[2] = 3;
   var_dump(count($array), array_sum($array));
   Code
   Trick #2
   Sum Sum Sum
   

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9. int(3)
   int(0)
   int(3)
   int(9)
   Output
   Trick #2
   Sum Sum Sum
   

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10. Trick #3
    EvilVar
    

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11. // Insert Magic Code Here (4 lines)
    eval($$$$var);
    Code
    Hello World
    Output
    Trick #3
    EvilVar
    

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12. Trick #4
    Weird assignment
    

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13. Trick #4
    Weird assignment
    // Insert Magic Code Here (10 lines)
    $var = 'Hello!';
    echo $var;
    Code
    World!
    Output
    

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14. Trick #5
    Count on me
    

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15. Trick #5
    Count on me
    // Insert Magic Code Here
    for ($i = 0; $i <= count($data); $i++){
    $data++;
    }
    echo $data;
    Code
    Hello
    Output
    

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16. Trick #6
    PHP in the middle
    

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17. Trick #6
    PHP in the middle
    // Insert Magic Code Here (6 lines)
    echo 'Hello';
    echo 'World';
    Code
    Hello PHP World
    Output
    

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18. Trick #7
    Mad World
    

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19. Trick #7
    Mad World
    // Insert Magic Code Here (3 lines)
    echo 'Foobar';
    echo PHP_EOL;
    echo 'Hello World';
    Code
    dlroW olleH
    rabooF
    Output
    

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20. RULES
    

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21. • replace „Insert Magic Code Here“ comments
    • no script termination
    return, exit, die, __halt_compiler, etc…
    • all lines executed on runtime
    • no additional eval
    RULES
    

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22. • Fork github.com/chr-hertel/php-magic-tricks
    • Your solutions as pull request
    • My solutions later tonight
    RULES
    

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23. CREDITS
    

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24. all anonymous
    PHP devs on 3V4L.org
    

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