Add use-package-tags-load function

Author: akirak

use-package-tags.el

@@ -290,5 +290,40 @@ If SORT is non-nil, the result will be lexicographically sorted."
            (cl-remove-duplicates)
            (order)))))
 
+(defun use-package-tags--unloaded-tags ()
+  "Return a list of tags that are not in the current profile."
+  (-difference (use-package-tags-collect-tags t :sort t)
+               use-package-tags-current-profile))
+
+;;;###autoload
+(defun use-package-tags-load (tag)
+  "Load packages with a TAG.
+
+This function evalates `use-package' forms with the selected tag
+in `use-package-tags-init-files'.
+
+After successfully loading all matching packages, the tag will be
+added to `use-package-tags-current-profile', without saving the value
+to `custom-file'."
+  (interactive (list (intern (completing-read "Load packages with tag: "
+                                              (use-package-tags--unloaded-tags)
+                                              nil 'match))))
+  (cl-labels
+      ((get-keyword (prop rest) (-some->> (member prop rest)
+                                  (nth 1)))
+       (has-tag-p (tag rest)
+                  (let ((tags (cdr (get-keyword :tags rest))))
+                    (memq tag (cl-etypecase tags
+                                (list tags)
+                                (symbol (list tags)))))))
+    (use-package-tags--with-package-forms
+        (use-package-tags--source-buffer-list t)
+      (let ((exp (read (current-buffer))))
+        (when (has-tag-p tag exp)
+          (message "Loading package %s configured at %s..."
+                   (nth 1 exp)
+                   (abbreviate-file-name (buffer-file-name)))
+          (eval exp))))))
+
 (provide 'use-package-tags)
 ;;; use-package-tags.el ends here