I have found a peculiar issue with PHP’s json_encode() function.
If you have an instance object with private properties and use json_encode() it will give you a very misleading warning.
class ExampleObject {
private $privateProperty;
...
}
$obj = new ExampleObject();
json_encode($obj);
results in
Warning: json_encode() … recursion detected …
There are two workarounds in the comments for the function at php.net but this is simply a PHP bug as far as I am concerned.