How can PHP developers effectively manage external scripts like counters to prevent syntax errors in JavaScript?

To effectively manage external scripts like counters in PHP, developers can use the `json_encode()` function to encode the data in PHP before passing it to JavaScript. This helps prevent syntax errors that may occur when passing complex data structures from PHP to JavaScript.

<?php
$counter = array(
    'total_visits' => 1000,
    'unique_visitors' => 500
);

$counter_json = json_encode($counter);
?>

<script>
var counterData = <?php echo $counter_json; ?>;
console.log(counterData);
</script>