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Discussion on: Reverse a string: awful answers only

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Gary Bell • • Edited 
function reverseString(string $input): string
{
    $reverseCode = '';
    for ($i = strlen($input) -1; $i >= 0; $i--) {
        //$reverseCode .= 'substr("' . str_replace("'", "\'", $input) . '", ' . $i . ', 1) . ';
        $reverseCode .= 'substr(\"' . $input . '\", ' . $i . ', 1) . ';
    }
    $reverseCode .= '\"\";';
    $reversedString = exec("php -r \"echo $reverseCode\"");
    return $reversedString;
}
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Ok, so this monstrosity uses the built-in substr method. But instead of using that to determine the string, it builds a whole bund of PHP code to execute within the shell, calls that via exec, and returns the string.

Awfully bad practice, inefficient, and dangerous. It's the type of code which gives PHP a bad name!