I am not sure to understand why
require_once is preferred to
require. It is said :
Because including the same file multiple times could have unpredictable results, the “once” versions are preferred.
But if we know how and when the code is used, we should know that one file will be included one or more times isn’t it?
Require_once adds a condition to know if the file has been loaded but if we already know that …why ask PHP for the solution we already have?