imenu selection buffer

lisp/imenu-selection-buffer.el

@@ -0,0 +1,36 @@
+;; This buffer is for text that is not saved, and for Lisp evaluation.
+;; To create a file, visit it with ‘C-x C-f’ and enter text in its buffer.
+
+(define-derived-mode imenu-selection-mode fundamental-mode "imenu"
+  "Major mode for imenu selection."
+  (suppress-keymap imenu-selection-mode-map)
+  (define-key imenu-selection-mode-map "j" 'next-line)
+  (define-key imenu-selection-mode-map "k" 'previous-line)
+  (define-key imenu-selection-mode-map "l" 'imenu-selection-select)
+  (define-key imenu-selection-mode-map "\C-m" 'imenu-selection-select)
+  (define-key imenu-selection-mode-map "h" 'kill-this-buffer)
+  )
+(defvar imenu--selection-buffer " *imenu-select*")
+(defvar imenu--target-buffer nil)
+(defun imenu-make-selection-buffer (&optional index-alist)
+  (interactive)
+  (require 'which-func)
+  (setq index-alist (if index-alist index-alist (imenu--make-index-alist)))
+  (let ((cur (which-function)))
+    (when (listp cur)
+      (setq cur (car cur)))
+    (setq imenu--target-buffer (current-buffer))
+    (switch-to-buffer imenu--selection-buffer)
+    (buffer-disable-undo)
+    (erase-buffer)
+    (dolist (x index-alist)
+      (insert (car x) "\n"))
+    (if cur (search-backward (concat cur "\n") nil t))
+    (imenu-selection-mode)))
+
+(defun imenu-selection-select ()
+  (interactive)
+  (let ((sel (substring (thing-at-point 'line) 0 -1)))
+    (bury-buffer)
+    (switch-to-buffer imenu--target-buffer)
+    (imenu sel)))