Non-recursive filter-files-in-directory

ffd.el

(defun filter-files-in-directory (dir &optional filter include-subdirs)
  (let ((dirs (list dir))
        (result '()))
    (while dirs
      (dolist (f (directory-files (pop dirs) 'full nil 'nosort))
        (cond ((string-match "/\\([.][.]?\\|.git\\)$" f)
               ;; do nothing if ".", "..", or ".git"
               )
              ((and include-subdirs (file-directory-p f))
               (push f dirs))
              ((or (null filter)
                   (if (stringp filter)
                       (string-match filter f)
                     (funcall filter f)))
               (push f result)))))
    result))