git clone https://github.com/honmaple/emacs-maple-imenu ~/.emacs.d/site-lisp/maple-imenu(require 'maple-imenu)
(setq maple-imenu-display-alist '((side . left) (slot . -1)))
(evil-leader/set-key "bi" 'maple-imenu)
;; with use-package
(use-package maple-imenu
:ensure nil
:commands (maple-imenu)
:config
(setq maple-imenu-display-alist '((side . left) (slot . -1))))