Fix obsolete (when|if)-let messages in Emacs 26

modules/app/email/config.el

@@ -31,7 +31,7 @@ DEFAULT-P is a boolean. If non-nil, it marks that email account as the
 default/fallback account."
   `(after! mu4e
      (let ((account-vars ,letvars))
-       (when-let (address (cdr (assq 'user-mail-address account-vars)))
+       (when-let* ((address (cdr (assq 'user-mail-address account-vars))))
          (cl-pushnew address mu4e-user-mail-address-list :test #'equal))
        (let ((context (make-mu4e-context
                        :name ,label

modules/app/irc/config.el

@@ -88,7 +88,7 @@ playback.")
 
   (defun +irc*circe-truncate-nicks ()
     "Truncate long nicknames in chat output non-destructively."
-    (when-let (beg (text-property-any (point-min) (point-max) 'lui-format-argument 'nick))
+    (when-let* ((beg (text-property-any (point-min) (point-max) 'lui-format-argument 'nick)))
       (goto-char beg)
       (let ((end (next-single-property-change beg 'lui-format-argument))
             (nick (plist-get (plist-get (text-properties-at beg) 'lui-keywords)

modules/app/regex/autoload/regex.el

@@ -261,7 +261,7 @@ __DATA__
           (overlay-put ov 'category '+regex))
         (cl-incf i)
         (dotimes (i 10)
-          (when-let (text (match-string i))
+          (when-let* ((text (match-string i)))
             (save-match-data
               (with-current-buffer +regex--groups-buffer
                 (goto-char (point-max))

modules/app/rss/autoload.el

@@ -11,7 +11,7 @@
   (interactive)
   (doom-kill-matching-buffers "^\\*elfeed")
   (dolist (file +rss-elfeed-files)
-    (when-let (buf (get-file-buffer (expand-file-name file +rss-org-dir)))
+    (when-let* ((buf (get-file-buffer (expand-file-name file +rss-org-dir))))
       (kill-buffer buf))))
 
 ;;;###autoload