From what I can see, the problem is that the variables in the parameters ($post_id
, $prefix
, …) have not been defined. In PHP, that means they have the type null
. However, in the last version, I made things a bit stricter to only allow int
and string
types, respectively, to avoid unexpected outcomes. Always make sure to have variables defined; otherwise, try not to use them in parameters of functions. This will lead to errors like this ??
Kindly let me know if the latest development version worked out for you. If not, please erase your debug.log
and show me the newly generated one so I can inspect the bug.