如何首先使用scandir对文件夹进行排序并使用usort [duplicate]

Question

This question already has an answer here:

• How to rewrite an example without the use of create_function? 1 answer
• PHP 7.2 Function create_function() is deprecated 4 answers

For a filemanagement, I use create_function to sort folders(directories) first and then files. But it seems that create_function is deprecated in php 7.2.

So how can I use the usort below correctly?

 $files = array_diff( scandir($dir), array(".", "..", "tmp") );

 usort ($files, create_function ('$a,$b', '
  return    is_dir ($a)
    ? (is_dir ($b) ? strnatcasecmp ($a, $b) : -1)
    : (is_dir ($b) ? 1 : (
        strcasecmp (pathinfo ($a, PATHINFO_EXTENSION), pathinfo ($b, PATHINFO_EXTENSION)) == 0
        ? strnatcasecmp ($a, $b)
        : strcasecmp (pathinfo ($a, PATHINFO_EXTENSION), pathinfo ($b, PATHINFO_EXTENSION))
    ))
  ;
'));

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