Why is the function not being executed?

Question

PHP

We have such a PHP script that gives javascript:

<?php
require_once($_SERVER['DOCUMENT_ROOT'] . "/core/config.php");
require_once(ABSPATH . "core/functions.php");

header("Content-type: application/javascript; charset=utf-8");

?>
<?php

// вот тут проблема.
// функция не выполняется
// нв выходе получаем строку is_auth = ;
// а должно быть true или false
echo "is_auth = ".is_auth().";\r\n";

?>
$(document).ready(function(){
  /*
  *	ОБРАБОТЧИКИ
  */
  // еще куча кода
  // кстати PHP константы нормально выводятся в контексте js

I believe it's because header("Content-type: application/javascript; charset=utf-8");
I'm right? What to do?

Answer 1

That's right. Look at the output of the command "echo false;" - empty line.

php > echo "is_auth = " . false . ";\r\n";
is_auth = ;
php > echo "is_auth = " . json_encode(false) . ";\r\n";
is_auth = false;

EDIT
php.net/manual/en/language.types.string.php#langua...
A boolean TRUE value is converted to the string "1". Boolean FALSE is converted to "" (the empty string). This allows conversion back and forth between boolean and string values.