using require

lisp/init-imenu.el

@@ -0,0 +1,62 @@
+;;; ** load imenu
+(require 'imenu)
+(define-key global-map [C-down-mouse-2] 'imenu)
+
+;; via https://superuser.com/questions/601982/how-to-quickly-navigate-jump-between-functions-on-emacs
+(defun ido-imenu ()
+  "Update the imenu index and then use ido to select a symbol to navigate to.
+Symbols matching the text at point are put first in the completion list."
+  (interactive)
+  (imenu--make-index-alist)
+  (let ((name-and-pos '())
+        (symbol-names '()))
+    (flet ((addsymbols
+            (symbol-list)
+            (when (listp symbol-list)
+              (dolist (symbol symbol-list)
+                (let ((name nil) (position nil))
+                  (cond
+                   ((and (listp symbol) (imenu--subalist-p symbol))
+                    (addsymbols symbol))
+
+                   ((listp symbol)
+                    (setq name (car symbol))
+                    (setq position (cdr symbol)))
+
+                   ((stringp symbol)
+                    (setq name symbol)
+                    (setq position
+                          (get-text-property 1 'org-imenu-marker symbol))))
+
+                  (unless (or (null position) (null name))
+                    (add-to-list 'symbol-names name)
+                    (add-to-list 'name-and-pos (cons name position))))))))
+      (addsymbols imenu--index-alist))
+    ;; If there are matching symbols at point, put them at the beginning
+    ;; of `symbol-names'.
+    (let ((symbol-at-point (thing-at-point 'symbol)))
+      (when symbol-at-point
+        (let* ((regexp (concat (regexp-quote symbol-at-point) "$"))
+               (matching-symbols
+                (delq nil (mapcar
+                           (lambda (symbol)
+                             (if (string-match regexp symbol) symbol))
+                           symbol-names))))
+          (when matching-symbols
+            (sort matching-symbols (lambda (a b) (> (length a) (length b))))
+            (mapc
+             (lambda (symbol)
+               (setq symbol-names (cons symbol (delete symbol symbol-names))))
+             matching-symbols)))))
+    (let* ((selected-symbol (ido-completing-read "Symbol? " symbol-names))
+           (position (cdr (assoc selected-symbol name-and-pos))))
+      (push-mark)
+      (if (overlayp position)
+          (goto-char (overlay-start position))
+        (goto-char position)))))
+
+(global-set-key (kbd "C-c C-j") 'ido-imenu)
+
+
+(provide 'init-imenu)
+;;; init-imenu.el ends here