Memory managment

[YuriOsokin]

I am parsing two JSON file one after another.

parser = JSON_Parser();
[obj, errors] = parser.parse(File1,'Schema.json');
clear parser.configParam, delete(parser), clear parser
parser = JSON_Parser();
[obj, errors] = parser.parse(File2,'Schema.json');

On the second time I parse, the object has some memory regarding its positionin schema. Clear all, clear classes, delete(parser), and clearing persistent variable 'clear parser.configParam' does not help.
It seems that the problem is in the persistent variable 'config' in the static function 'configParam' of the JSON class. But still, I am not sure.
Could you please see what the issue is?