What are the limitations of using regular expressions to parse PHP code in a forum setting?

Using regular expressions to parse PHP code in a forum setting can be limited because PHP code can be complex and varied, making it difficult to accurately capture all possible scenarios with regular expressions. Additionally, regular expressions may not be able to handle nested structures or handle edge cases effectively. To overcome these limitations, it is recommended to use a parser specifically designed for PHP code, such as the PHP-Parser library, which can accurately parse and analyze PHP code in a more robust manner.

// Example of using PHP-Parser library to parse PHP code in a forum setting
require_once 'vendor/autoload.php';

$code = '<?php echo "Hello, World!"; ?>';

$parser = (new PhpParser\ParserFactory)->create(PhpParser\ParserFactory::PREFER_PHP7);
$traverser = new PhpParser\NodeTraverser;
$traverser->addVisitor(new PhpParser\NodeVisitor\NameResolver);
$traverser->addVisitor(new PhpParser\NodeVisitor\CloningVisitor);
$ast = $parser->parse($code);

// Traverse and analyze the parsed PHP code AST
$traverser->traverse($ast);

// Further processing and analysis of the parsed PHP code