How can the use of regular expressions (like preg_replace) impact performance when replacing placeholders in PHP templates?

Using regular expressions like preg_replace to replace placeholders in PHP templates can impact performance because regular expressions are computationally expensive compared to simple string replacements. To improve performance, it's recommended to use str_replace or strtr functions for simple placeholder replacements in PHP templates.

// Example of using str_replace for simple placeholder replacement in PHP template
$template = "Hello, {name}!";
$replacements = array('{name}' => 'John');
echo str_replace(array_keys($replacements), array_values($replacements), $template);