Question

Without using include_once or any include/require how can I reference functions declared in other php files in the current directory? Just like we use fopen.

Including contents of php files which contain code not in functions can be a clutter. It’d be better if function usage is linked automatically to its definition.

I’ve also checked How to include() all PHP files from a directory? which requires some code to do it.

I’m not able to find answer of this anywhere in internet may be because of too common search terms for this problem.

Answer 1

You can use glob to traverse the directory and then include them:

$phpfiles = glob('mydir/*.php');
foreach($phpfiles as $file)
  do_something_with_the_file($file) // why not include_once $file ?

As you are referencing functions in other files, you cannot use the autoloader because the autoloader operates on classes. Autoloading classes would be a much better solution.