Returns FALSE for an internal function (when isInternal() returns TRUE, e.g. for 'strlen').
(PHP 5 >= 5.2.0, PHP 7, PHP 8)
ReflectionFunctionAbstract::getFileName — Gets file name
Gets the file name from a user-defined function.
This function has no parameters.
Returns the filename of the file in which the function has been defined.
If the class is defined in the PHP core or in a PHP extension, false
is returned.
Returns FALSE for an internal function (when isInternal() returns TRUE, e.g. for 'strlen').