The face function only takes the link path, which is a string. you cannot use org-element-property on it.

Maybe you want something like this:

#+begin_src emacs-lisp
(defun org-link-beautify-face (path)
  "Set link face colors."
  (message "beautifying")
  (if (and (not (file-remote-p path))
  (file-exists-p (expand-file-name path)))
      'org-link
    'org-warning))

;;; DEBUG
(org-link-set-parameters
 "file"
 :face #'org-link-beautify-face)
#+end_src

John

-----------------------------------
Professor John Kitchin 
Doherty Hall A207F
Department of Chemical Engineering
Carnegie Mellon University
Pittsburgh, PA 15213
412-268-7803


On Tue, May 19, 2020 at 9:12 AM stardiviner <numbchild@gmail.com> wrote:
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Bellowing is my source code, it does not work. I'm wondering why?

#+begin_src emacs-lisp
(defun org-link-beautify-face (link)
  "Set link face colors."
  (let ((raw-link (org-element-property :raw-link link))
        (type (org-element-property :type link))
        (path (org-element-property :path link)))
    (pcase type
      ;; ("https" )
      ;; ("http" )
      ("file"
       (if (and (not (file-remote-p path))
                (file-exists-p (expand-file-name path)))
           'org-link 'org-warning)))))

;;; DEBUG
(org-link-set-parameters
 "file"
 :face #'org-link-beautify-face)
#+end_src

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[ stardiviner ]
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