Non PHP Config Files in CodeIgniter 3

Is there a clean way of replacing the PHP config files in CodeIgniter 3 with a different format like JSON or TOML without having to type in the location of the value for each variable in the PHP file? Is this even a good idea?

You can do everything what you want if you have time and skills but why you wanna change config to json? If you do this you must track every call to var in your config.php and change this or write something like wrapper. When new version of CI will be available you start from beginning. This is bad idea.