How can the use of heredoc syntax in PHP lead to errors like unexpected end of file?

Using heredoc syntax in PHP can lead to errors like "unexpected end of file" if there are any syntax errors within the heredoc block, such as missing closing tags or mismatched quotes. To solve this issue, make sure that the heredoc block is properly formatted with correct opening and closing tags, and ensure that there are no syntax errors within the block.

// Correctly formatted heredoc block
$heredoc = <<<EOD
This is a heredoc block.
It can span multiple lines.
EOD;

echo $heredoc;