Variable: cider-tree-view--header-fn
cider-tree-view--header-fn is a buffer-local variable defined in
cider-tree-view.el.
Documentation
When non-nil, a function of no arguments that inserts content above the tree.
It runs on every (re-)render, so a consumer can show controls - filter toggles, say - that survive expand/collapse.
Source Code
;; Defined in ~/.emacs.d/elpa/cider-20260822.1520/cider-tree-view.el
(defvar-local cider-tree-view--header-fn nil
"When non-nil, a function of no arguments that inserts content above the tree.
It runs on every (re-)render, so a consumer can show controls - filter toggles,
say - that survive expand/collapse.")