A PHP Error was encountered

Severity: 8192

Message: ctype_digit(): Argument of type null will be interpreted as string in the future

Filename: libraries/Pagination.php

Line Number: 526

Backtrace:

File: /opt/lampp/htdocs/liberator/application/helpers/app_data_helper.php
Line: 57
Function: create_links

File: /opt/lampp/htdocs/liberator/application/controllers/Research.php
Line: 168
Function: get_pagination

File: /opt/lampp/htdocs/liberator/index.php
Line: 315
Function: require_once