graph-validator-post: reject invalid input
:: +notification-kind: no notifications for now
::
++ notification-kind ~
+ ++ transform-add-nodes
+ |= [=index =post =atom was-parent-modified=?]
+ ^- [^index ^post]
+ =- [- post(index -)]
+ ?~ index !!
+ ?: ?=([@ ~] index)
+ [atom ~]
+ ?: was-parent-modified
+ ~|(%cannot-submit-parents-with-prepopulated-children !!)
+ `^index`(snoc `^index`(snip index) atom)
--
++ grab
|%
