emacs: Add 'guix-root-map'.

* emacs/guix-base.el (guix-define-buffer-type): Move common key bindings
  from here...
  (guix-root-map): ... to here.  New variable.
* emacs/guix-info.el (guix-info-mode-map): Use it.
* emacs/guix-list.el (guix-list-mode-map): Use it.
* doc/emacs.texi (Emacs Keymaps): Document it.

doc/emacs.texi

@@ -426,6 +426,9 @@ If you want to change default key bindings, use the following keymaps
 (@pxref{Init Rebinding,,, emacs, The GNU Emacs Manual}):
 
 @table @code
+@item guix-root-map
+Parent keymap with general keys for all guix modes.
+
 @item guix-list-mode-map
 Parent keymap with general keys for ``list'' buffers.
 

emacs/guix-base.el

@@ -295,6 +295,17 @@ See `guix-update-after-operation' for details."
 
 ;;; Common definitions for buffer types
 
+(defvar guix-root-map
+  (let ((map (make-sparse-keymap)))
+    (define-key map (kbd "l") 'guix-history-back)
+    (define-key map (kbd "r") 'guix-history-forward)
+    (define-key map (kbd "g") 'revert-buffer)
+    (define-key map (kbd "R") 'guix-redisplay-buffer)
+    (define-key map (kbd "M") 'guix-apply-manifest)
+    (define-key map (kbd "C-c C-z") 'guix-switch-to-repl)
+    map)
+  "Parent keymap for all guix modes.")
+
 (defvar-local guix-profile nil
   "Profile used for the current buffer.")
 (put 'guix-profile 'permanent-local t)
@@ -440,15 +451,7 @@ following keywords are available:
                   "\\{" mode-map-str "}")
          (setq-local revert-buffer-function 'guix-revert-buffer)
          (setq-local guix-history-size ,history-var)
-         (and (fboundp ',mode-init-fun) (,mode-init-fun)))
-
-       (let ((map ,mode-map))
-         (define-key map (kbd "l") 'guix-history-back)
-         (define-key map (kbd "r") 'guix-history-forward)
-         (define-key map (kbd "g") 'revert-buffer)
-         (define-key map (kbd "R") 'guix-redisplay-buffer)
-         (define-key map (kbd "M") 'guix-apply-manifest)
-         (define-key map (kbd "C-c C-z") 'guix-switch-to-repl)))))
+         (and (fboundp ',mode-init-fun) (,mode-init-fun))))))
 
 (put 'guix-define-buffer-type 'lisp-indent-function 'defun)
 

emacs/guix-info.el

@@ -395,7 +395,7 @@ See `insert-text-button' for the meaning of PROPERTIES."
 (defvar guix-info-mode-map
   (let ((map (make-sparse-keymap)))
     (set-keymap-parent
-     map (make-composed-keymap button-buffer-map
+     map (make-composed-keymap (list guix-root-map button-buffer-map)
                                special-mode-map))
     map)
   "Parent keymap for info buffers.")

emacs/guix-list.el

@@ -371,7 +371,9 @@ Same as `tabulated-list-sort', but also restore marks after sorting."
 
 (defvar guix-list-mode-map
   (let ((map (make-sparse-keymap)))
-    (set-keymap-parent map tabulated-list-mode-map)
+    (set-keymap-parent
+     map (make-composed-keymap guix-root-map
+                               tabulated-list-mode-map))
     (define-key map (kbd "RET") 'guix-list-describe)
     (define-key map (kbd "m")   'guix-list-mark)
     (define-key map (kbd "*")   'guix-list-mark)