emacs: Reorganize package/generation UI code.

Move the code for packages/generations interface from "guix-info.el",
"guix-list.el", "guix-base.el" and "guix.el" to "guix-ui-package.el" and
"guix-ui-generation.el".

* emacs/guix-base.el (guix-package-entry->name-specification)
  (guix-package-entries->name-specifications)
  (guix-package-id-and-output-by-output-id)
  (guix-package-installed-outputs, guix-process-package-actions)
  (guix-package-list-type, guix-package-info-type)
  (guix-continue-package-operation-p, guix-get-package-strings)
  (guix-insert-package-strings): Move to "guix-ui-package.el".
  (guix-generation-packages-buffer-name-function, guix-output-name-width)
  (guix-generation-packages-update-buffer, guix-generation-packages)
  (guix-generation-packages-buffer-name-default)
  (guix-generation-packages-buffer-name-long)
  (guix-generation-packages-buffer-name, guix-generation-packages-buffer)
  (guix-generation-insert-packages, guix-generation-insert-package)
  (guix-profile-generation-manifest-file, guix-delete-generations)
  (guix-profile-generation-packages-buffer, guix-switch-to-generation):
  Move to "guix-ui-generation.el".
* emacs/guix-info.el (guix-package-location, guix-package-name)
  (guix-package-source, guix-package-info-source)
  (guix-package-info-heading, guix-package-info-license)
  (guix-package-info-name, guix-package-info-name-button)
  (guix-package-info-version, guix-package-info-location)
  (guix-package-info-synopsis, guix-package-info-description)
  (guix-package-info-obsolete, guix-package-info-installed-outputs)
  (guix-package-info-uninstalled-outputs)
  (guix-package-info-insert-heading)
  (guix-package-info-define-insert-inputs)
  (guix-package-info-obsolete-string)
  (guix-package-info-insert-obsolete-text)
  (guix-package-info-insert-non-unique-text)
  (guix-package-info-insert-outputs, guix-package-info-insert-output)
  (guix-package-info-insert-action-button)
  (guix-package-info-auto-find-source)
  (guix-package-info-auto-download-source)
  (guix-package-info-download-buffer, guix-package-info-show-source)
  (guix-package-info-download-source, guix-package-info-insert-source)
  (guix-package-info-redisplay-after-download)
  (guix-output-info-insert-version, guix-output-info-insert-output):
  Move to "guix-ui-package.el".
  (guix-generation-info-number, guix-generation-info-current)
  (guix-generation-not-current, guix-generation-info-insert-number)
  (guix-generation-info-insert-current): Move to "guix-ui-generation.el".
* emacs/guix-list.el (guix-package-list-generation-marking-enabled)
  (guix-package-list-installed, guix-package-list-obsolete)
  (guix-package-list-get-name, guix-package-list-get-installed-outputs)
  (guix-package-list-marking-check, guix-package-list-mark-outputs)
  (guix-package-list-mark-install, guix-package-list-mark-delete)
  (guix-package-list-mark-upgrade, guix-package-list-mark-upgrades)
  (guix-list-mark-package-upgrades, guix-list-execute-package-actions)
  (guix-package-list-execute, guix-package-list-make-action)
  (guix-package-list-edit, guix-output-list-mark-install)
  (guix-output-list-mark-delete, guix-output-list-mark-upgrade)
  (guix-output-list-mark-upgrades, guix-output-list-make-action)
  (guix-output-list-describe, guix-output-list-edit): Move to
  "guix-ui-package.el".
  (guix-generation-list-get-current, guix-generation-list-switch)
  (guix-generation-list-generations-to-compare)
  (guix-generation-list-compare, guix-generation-list-show-packages)
  (guix-generation-list-show-added-packages)
  (guix-generation-list-show-removed-packages)
  (guix-generation-list-diff, guix-generation-list-diff-manifests)
  (guix-generation-list-ediff, guix-generation-list-ediff-manifests)
  (guix-generation-list-diff-packages)
  (guix-generation-list-ediff-packages)
  (guix-generation-list-mark-delete, guix-generation-list-execute): Move
  to "guix-ui-generation.el".
* emacs/guix.el: Remove.
  (guix, guix-faces, guix-edit): Move to "guix-base.el".
  (guix-list-single-package, guix-search-params, guix-search-history)
  (guix-get-show-packages, guix-search-by-name, guix-search-by-regexp)
  (guix-installed-packages, guix-obsolete-packages)
  (guix-all-available-packages, guix-newest-available-packages): Move
  to "guix-ui-package.el".
  (guix-get-show-generations, guix-generations, guix-last-generations)
  (guix-generations-by-time): Move to "guix-ui-generation.el".
* emacs.am (ELFILES): Remove "guix.el".  Add "guix-ui-package.el" and
  "guix-ui-generation.el".
* doc/emacs.texi (Emacs Appearance): Adjust accordingly.

8 files changed, 1428 insertions, 1383 deletions

diff --git a/doc/emacs.texi b/doc/emacs.texi
index ff866947c0..6b989a976d 100644
--- a/doc/emacs.texi
+++ b/doc/emacs.texi
@@ -160,7 +160,7 @@ Display package(s) with the specified name.
 @item M-x guix-search-by-regexp
 Search for packages by a specified regexp.  By default ``name'',
 ``synopsis'' and ``description'' of the packages will be searched.  This
-can be changed by modifying @code{guix-search-params} variable.
+can be changed by modifying @code{guix-package-search-params} variable.
 
 @end table
 
diff --git a/emacs.am b/emacs.am
index 7848b1c415..bfd9494b0a 100644
--- a/emacs.am
+++ b/emacs.am
@@ -42,8 +42,9 @@ ELFILES =					\
   emacs/guix-profiles.el			\
   emacs/guix-read.el				\
   emacs/guix-ui.el				\
-  emacs/guix-utils.el				\
-  emacs/guix.el
+  emacs/guix-ui-package.el			\
+  emacs/guix-ui-generation.el			\
+  emacs/guix-utils.el
 
 if HAVE_EMACS
 
diff --git a/emacs/guix-base.el b/emacs/guix-base.el
index ab8acdfb31..dae658ebfa 100644
--- a/emacs/guix-base.el
+++ b/emacs/guix-base.el
@@ -25,50 +25,29 @@
 ;;; Code:
 
 (require 'cl-lib)
-(require 'guix-profiles)
 (require 'guix-backend)
-(require 'guix-entry)
 (require 'guix-guile)
+(require 'guix-read)
 (require 'guix-utils)
 (require 'guix-ui)
 
-
-;;; Parameters of the entries
+(defgroup guix nil
+  "Settings for Guix package manager and friends."
+  :prefix "guix-"
+  :group 'external)
+
+(defgroup guix-faces nil
+  "Guix faces."
+  :group 'guix
+  :group 'faces)
 
 (defun guix-package-name-specification (name version &optional output)
   "Return Guix package specification by its NAME, VERSION and OUTPUT."
   (concat name "-" version
           (when output (concat ":" output))))
 
-(defun guix-package-entry->name-specification (entry &optional output)
-  "Return name specification of the package ENTRY and OUTPUT."
-  (guix-package-name-specification
-   (guix-entry-value entry 'name)
-   (guix-entry-value entry 'version)
-   (or output (guix-entry-value entry 'output))))
-
-(defun guix-package-entries->name-specifications (entries)
-  "Return name specifications by the package or output ENTRIES."
-  (cl-remove-duplicates (mapcar #'guix-package-entry->name-specification
-                                entries)
-                        :test #'string=))
-
-(defun guix-package-installed-outputs (entry)
-  "Return list of installed outputs for the package ENTRY."
-  (mapcar (lambda (installed-entry)
-            (guix-entry-value installed-entry 'output))
-          (guix-entry-value entry 'installed)))
-
-(defun guix-package-id-and-output-by-output-id (oid)
-  "Return list (PACKAGE-ID OUTPUT) by output id OID."
-  (cl-multiple-value-bind (pid-str output)
-      (split-string oid ":")
-    (let ((pid (string-to-number pid-str)))
-      (list (if (= 0 pid) pid-str pid)
-            output))))
-
 
-;;; Location of the packages
+;;; Location of packages, profiles and manifests
 
 (defvar guix-directory nil
   "Default Guix directory.
@@ -108,56 +87,6 @@ For the meaning of location, see `guix-find-location'."
   (guix-eval-read (guix-make-guile-expression
                    'package-location-string id-or-name)))
 
-
-;;; Getting and displaying info about packages and generations
-
-(defcustom guix-package-list-type 'output
-  "Define how to display packages in a list buffer.
-May be a symbol `package' or `output' (if `output', display each
-output on a separate line; if `package', display each package on
-a separate line)."
-  :type '(choice (const :tag "List of packages" package)
-                 (const :tag "List of outputs" output))
-  :group 'guix)
-
-(defcustom guix-package-info-type 'package
-  "Define how to display packages in an info buffer.
-May be a symbol `package' or `output' (if `output', display each
-output separately; if `package', display outputs inside a package
-information)."
-  :type '(choice (const :tag "Display packages" package)
-                 (const :tag "Display outputs" output))
-  :group 'guix)
-
-
-;;; Generations
-
-(defcustom guix-generation-packages-buffer-name-function
-  #'guix-generation-packages-buffer-name-default
-  "Function used to define name of a buffer with generation packages.
-This function is called with 2 arguments: PROFILE (string) and
-GENERATION (number)."
-  :type '(choice (function-item guix-generation-packages-buffer-name-default)
-                 (function-item guix-generation-packages-buffer-name-long)
-                 (function :tag "Other function"))
-  :group 'guix)
-
-(defcustom guix-generation-packages-update-buffer t
-  "If non-nil, always update list of packages during comparing generations.
-If nil, generation packages are received only once.  So when you
-compare generation 1 and generation 2, the packages for both
-generations will be received.  Then if you compare generation 1
-and generation 3, only the packages for generation 3 will be
-received.  Thus if you use comparing of different generations a
-lot, you may set this variable to nil to improve the
-performance."
-  :type 'boolean
-  :group 'guix)
-
-(defvar guix-output-name-width 30
-  "Width of an output name \"column\".
-This variable is used in auxiliary buffers for comparing generations.")
-
 (defun guix-generation-file (profile generation)
   "Return the file name of a PROFILE's GENERATION."
   (format "%s-%s-link" profile generation))
@@ -171,75 +100,14 @@ this generation."
                         (guix-generation-file profile generation)
                       profile)))
 
-(defun guix-generation-packages (profile generation)
-  "Return a list of sorted packages installed in PROFILE's GENERATION.
-Each element of the list is a list of the package specification and its path."
-  (let ((names+paths (guix-eval-read
-                      (guix-make-guile-expression
-                       'generation-package-specifications+paths
-                       profile generation))))
-    (sort names+paths
-          (lambda (a b)
-            (string< (car a) (car b))))))
-
-(defun guix-generation-packages-buffer-name-default (profile generation)
-  "Return name of a buffer for displaying GENERATION's package outputs.
-Use base name of PROFILE path."
-  (let ((profile-name (file-name-base (directory-file-name profile))))
-    (format "*Guix %s: generation %s*"
-            profile-name generation)))
-
-(defun guix-generation-packages-buffer-name-long (profile generation)
-  "Return name of a buffer for displaying GENERATION's package outputs.
-Use the full PROFILE path."
-  (format "*Guix generation %s (%s)*"
-          generation profile))
-
-(defun guix-generation-packages-buffer-name (profile generation)
-  "Return name of a buffer for displaying GENERATION's package outputs."
-  (let ((fun (if (functionp guix-generation-packages-buffer-name-function)
-                 guix-generation-packages-buffer-name-function
-               #'guix-generation-packages-buffer-name-default)))
-    (funcall fun profile generation)))
-
-(defun guix-generation-insert-package (name path)
-  "Insert package output NAME and PATH at point."
-  (insert name)
-  (indent-to guix-output-name-width 2)
-  (insert path "\n"))
-
-(defun guix-generation-insert-packages (buffer profile generation)
-  "Insert package outputs installed in PROFILE's GENERATION in BUFFER."
-  (with-current-buffer buffer
-    (setq buffer-read-only nil
-          indent-tabs-mode nil)
-    (erase-buffer)
-    (mapc (lambda (name+path)
-            (guix-generation-insert-package
-             (car name+path) (cadr name+path)))
-          (guix-generation-packages profile generation))))
-
-(defun guix-generation-packages-buffer (profile generation)
-  "Return buffer with package outputs installed in PROFILE's GENERATION.
-Create the buffer if needed."
-  (let ((buf-name (guix-generation-packages-buffer-name
-                   profile generation)))
-    (or (and (null guix-generation-packages-update-buffer)
-             (get-buffer buf-name))
-        (let ((buf (get-buffer-create buf-name)))
-          (guix-generation-insert-packages buf profile generation)
-          buf))))
-
-(defun guix-profile-generation-manifest-file (generation)
-  "Return the file name of a GENERATION's manifest.
-GENERATION is a generation number of the current profile."
-  (guix-manifest-file (guix-ui-current-profile) generation))
-
-(defun guix-profile-generation-packages-buffer (generation)
-  "Insert GENERATION's package outputs in a buffer and return it.
-GENERATION is a generation number of the current profile."
-  (guix-generation-packages-buffer (guix-ui-current-profile)
-                                   generation))
+;;;###autoload
+(defun guix-edit (id-or-name)
+  "Edit (go to location of) package with ID-OR-NAME."
+  (interactive (list (guix-read-package-name)))
+  (let ((loc (guix-package-location id-or-name)))
+    (if loc
+        (guix-find-location loc)
+      (message "Couldn't find package location."))))
 
 
 ;;; Actions on packages and generations
@@ -313,101 +181,6 @@ VARIABLE is a name of an option variable.")
       guix-operation-option-true-string
     guix-operation-option-false-string))
 
-(defun guix-process-package-actions (profile actions
-                                     &optional operation-buffer)
-  "Process package ACTIONS on PROFILE.
-Each action is a list of the form:
-
-  (ACTION-TYPE PACKAGE-SPEC ...)
-
-ACTION-TYPE is one of the following symbols: `install',
-`upgrade', `remove'/`delete'.
-PACKAGE-SPEC should have the following form: (ID [OUTPUT] ...)."
-  (let (install upgrade remove)
-    (mapc (lambda (action)
-            (let ((action-type (car action))
-                  (specs (cdr action)))
-              (cl-case action-type
-                (install (setq install (append install specs)))
-                (upgrade (setq upgrade (append upgrade specs)))
-                ((remove delete) (setq remove (append remove specs))))))
-          actions)
-    (when (guix-continue-package-operation-p
-           profile
-           :install install :upgrade upgrade :remove remove)
-      (guix-eval-in-repl
-       (guix-make-guile-expression
-        'process-package-actions profile
-        :install install :upgrade upgrade :remove remove
-        :use-substitutes? (or guix-use-substitutes 'f)
-        :dry-run? (or guix-dry-run 'f))
-       (and (not guix-dry-run) operation-buffer)))))
-
-(cl-defun guix-continue-package-operation-p (profile
-                                             &key install upgrade remove)
-  "Return non-nil if a package operation should be continued.
-Ask a user if needed (see `guix-operation-confirm').
-INSTALL, UPGRADE, REMOVE are 'package action specifications'.
-See `guix-process-package-actions' for details."
-  (or (null guix-operation-confirm)
-      (let* ((entries (guix-ui-get-entries
-                       profile 'package 'id
-                       (append (mapcar #'car install)
-                               (mapcar #'car upgrade)
-                               (mapcar #'car remove))
-                       '(id name version location)))
-             (install-strings (guix-get-package-strings install entries))
-             (upgrade-strings (guix-get-package-strings upgrade entries))
-             (remove-strings  (guix-get-package-strings remove entries)))
-        (if (or install-strings upgrade-strings remove-strings)
-            (let ((buf (get-buffer-create guix-temp-buffer-name)))
-              (with-current-buffer buf
-                (setq-local cursor-type nil)
-                (setq buffer-read-only nil)
-                (erase-buffer)
-                (insert "Profile: " profile "\n\n")
-                (guix-insert-package-strings install-strings "install")
-                (guix-insert-package-strings upgrade-strings "upgrade")
-                (guix-insert-package-strings remove-strings "remove")
-                (let ((win (temp-buffer-window-show
-                            buf
-                            '((display-buffer-reuse-window
-                               display-buffer-at-bottom)
-                              (window-height . fit-window-to-buffer)))))
-                  (prog1 (guix-operation-prompt)
-                    (quit-window nil win)))))
-          (message "Nothing to be done.  If the REPL was restarted, information is not up-to-date.")
-          nil))))
-
-(defun guix-get-package-strings (specs entries)
-  "Return short package descriptions for performing package actions.
-See `guix-process-package-actions' for the meaning of SPECS.
-ENTRIES is a list of package entries to get info about packages."
-  (delq nil
-        (mapcar
-         (lambda (spec)
-           (let* ((id (car spec))
-                  (outputs (cdr spec))
-                  (entry (guix-entry-by-id id entries)))
-             (when entry
-               (let ((location (guix-entry-value entry 'location)))
-                 (concat (guix-package-entry->name-specification entry)
-                         (when outputs
-                           (concat ":"
-                                   (guix-concat-strings outputs ",")))
-                         (when location
-                           (concat "\t(" location ")")))))))
-         specs)))
-
-(defun guix-insert-package-strings (strings action)
-  "Insert information STRINGS at point for performing package ACTION."
-  (when strings
-    (insert "Package(s) to " (propertize action 'face 'bold) ":\n")
-    (mapc (lambda (str)
-            (insert "  " str "\n"))
-          strings)
-    (insert "\n")))
-
 (defun guix-operation-prompt (&optional prompt)
   "Prompt a user for continuing the current operation.
 Return non-nil, if the operation should be continued; nil otherwise.
@@ -462,34 +235,6 @@ Ask a user with PROMPT for continuing an operation."
                  guix-operation-option-separator)))
   (force-mode-line-update))
 
-(defun guix-delete-generations (profile generations
-                                &optional operation-buffer)
-  "Delete GENERATIONS from PROFILE.
-Each element from GENERATIONS is a generation number."
-  (when (or (not guix-operation-confirm)
-            (y-or-n-p
-             (let ((count (length generations)))
-               (if (> count 1)
-                   (format "Delete %d generations from profile '%s'? "
-                           count profile)
-                 (format "Delete generation %d from profile '%s'? "
-                         (car generations) profile)))))
-    (guix-eval-in-repl
-     (guix-make-guile-expression
-      'delete-generations* profile generations)
-     operation-buffer)))
-
-(defun guix-switch-to-generation (profile generation
-                                  &optional operation-buffer)
-  "Switch PROFILE to GENERATION."
-  (when (or (not guix-operation-confirm)
-            (y-or-n-p (format "Switch profile '%s' to generation %d? "
-                              profile generation)))
-    (guix-eval-in-repl
-     (guix-make-guile-expression
-      'switch-to-generation* profile generation)
-     operation-buffer)))
-
 (defun guix-package-source-path (package-id)
   "Return a store file path to a source of a package PACKAGE-ID."
   (message "Calculating the source derivation ...")
diff --git a/emacs/guix-info.el b/emacs/guix-info.el
index 9c63892d06..5219ac5507 100644
--- a/emacs/guix-info.el
+++ b/emacs/guix-info.el
@@ -1,4 +1,4 @@
-;;; guix-info.el --- Info buffers for displaying entries   -*- lexical-binding: t -*-
+;;; guix-info.el --- 'Info' buffer interface for displaying data  -*- lexical-binding: t -*-
 
 ;; Copyright © 2014, 2015 Alex Kost <alezost@gmail.com>
 ;; Copyright © 2015 Ludovic Courtès <ludo@gnu.org>
@@ -20,15 +20,14 @@
 
 ;;; Commentary:
 
-;; This file provides a help-like buffer for displaying information
-;; about Guix packages and generations.
+;; This file provides 'info' (help-like) buffer interface for displaying
+;; an arbitrary data.
 
 ;;; Code:
 
-(require 'guix-base)
+(require 'guix-buffer)
 (require 'guix-entry)
 (require 'guix-utils)
-(require 'guix-ui)
 
 (defgroup guix-info nil
   "General settings for info buffers."
@@ -358,24 +357,6 @@ BUTTON-OR-FACE is a button type)."
   'action (lambda (btn)
             (browse-url (button-label btn))))
 
-(define-button-type 'guix-package-location
-  :supertype 'guix
-  'face 'guix-package-info-location
-  'help-echo "Find location of this package"
-  'action (lambda (btn)
-            (guix-find-location (button-label btn))))
-
-(define-button-type 'guix-package-name
-  :supertype 'guix
-  'face 'guix-package-info-name-button
-  'help-echo "Describe this package"
-  'action (lambda (btn)
-            (guix-buffer-get-display-entries-current
-             'info guix-package-info-type
-             (list (guix-ui-current-profile)
-                   'name (button-label btn))
-             'add)))
-
 (defun guix-info-button-copy-label (&optional pos)
   "Copy a label of the button at POS into kill ring.
 If POS is nil, use the current point position."
@@ -496,434 +477,6 @@ Print '%s' ENTRIES in the current 'info' buffer."
                    ,@%foreign-args))))))))
 
 
-;;; Displaying packages
-
-(guix-ui-info-define-interface package
-  :buffer-name "*Guix Package Info*"
-  :format '(guix-package-info-insert-heading
-            ignore
-            (synopsis ignore (simple guix-package-info-synopsis))
-            ignore
-            (description ignore (simple guix-package-info-description))
-            ignore
-            (outputs simple guix-package-info-insert-outputs)
-            (source simple guix-package-info-insert-source)
-            (location format (format guix-package-location))
-            (home-url format (format guix-url))
-            (license format (format guix-package-info-license))
-            (inputs format (format guix-package-input))
-            (native-inputs format (format guix-package-native-input))
-            (propagated-inputs format
-                               (format guix-package-propagated-input)))
-  :titles '((home-url . "Home page"))
-  :required '(id name version installed non-unique))
-
-(guix-info-define-interface installed-output
-  :format '((path simple (indent guix-file))
-            (dependencies simple (indent guix-file)))
-  :titles '((path . "Store directory"))
-  :reduced? t)
-
-(defface guix-package-info-heading
-  '((t :inherit guix-info-heading))
-  "Face for package name and version headings."
-  :group 'guix-package-info-faces)
-
-(defface guix-package-info-name
-  '((t :inherit font-lock-keyword-face))
-  "Face used for a name of a package."
-  :group 'guix-package-info-faces)
-
-(defface guix-package-info-name-button
-  '((t :inherit button))
-  "Face used for a full name that can be used to describe a package."
-  :group 'guix-package-info-faces)
-
-(defface guix-package-info-version
-  '((t :inherit font-lock-builtin-face))
-  "Face used for a version of a package."
-  :group 'guix-package-info-faces)
-
-(defface guix-package-info-synopsis
-  '((((type tty pc) (class color)) :weight bold)
-    (t :height 1.1 :weight bold :inherit variable-pitch))
-  "Face used for a synopsis of a package."
-  :group 'guix-package-info-faces)
-
-(defface guix-package-info-description
-  '((t))
-  "Face used for a description of a package."
-  :group 'guix-package-info-faces)
-
-(defface guix-package-info-license
-  '((t :inherit font-lock-string-face))
-  "Face used for a license of a package."
-  :group 'guix-package-info-faces)
-
-(defface guix-package-info-location
-  '((t :inherit link))
-  "Face used for a location of a package."
-  :group 'guix-package-info-faces)
-
-(defface guix-package-info-installed-outputs
-  '((default :weight bold)
-    (((class color) (min-colors 88) (background light))
-     :foreground "ForestGreen")
-    (((class color) (min-colors 88) (background dark))
-     :foreground "PaleGreen")
-    (((class color) (min-colors 8))
-     :foreground "green")
-    (t :underline t))
-  "Face used for installed outputs of a package."
-  :group 'guix-package-info-faces)
-
-(defface guix-package-info-uninstalled-outputs
-  '((t :weight bold))
-  "Face used for uninstalled outputs of a package."
-  :group 'guix-package-info-faces)
-
-(defface guix-package-info-obsolete
-  '((t :inherit error))
-  "Face used if a package is obsolete."
-  :group 'guix-package-info-faces)
-
-(defun guix-package-info-insert-heading (entry)
-  "Insert package ENTRY heading (name specification) at point."
-  (guix-insert-button
-   (guix-package-entry->name-specification entry)
-   'guix-package-name
-   'face 'guix-package-info-heading))
-
-(defmacro guix-package-info-define-insert-inputs (&optional type)
-  "Define a face and a function for inserting package inputs.
-TYPE is a type of inputs.
-Function name is `guix-package-info-insert-TYPE-inputs'.
-Face name is `guix-package-info-TYPE-inputs'."
-  (let* ((type-str (symbol-name type))
-         (type-name (and type (concat type-str "-")))
-         (type-desc (and type (concat type-str " ")))
-         (face (intern (concat "guix-package-info-" type-name "inputs")))
-         (btn  (intern (concat "guix-package-" type-name "input"))))
-    `(progn
-       (defface ,face
-         '((t :inherit guix-package-info-name-button))
-         ,(concat "Face used for " type-desc "inputs of a package.")
-         :group 'guix-package-info-faces)
-
-       (define-button-type ',btn
-         :supertype 'guix-package-name
-         'face ',face))))
-
-(guix-package-info-define-insert-inputs)
-(guix-package-info-define-insert-inputs native)
-(guix-package-info-define-insert-inputs propagated)
-
-
-;;; Inserting outputs and installed parameters
-
-(defvar guix-package-info-output-format "%-10s"
-  "String used to format output names of the packages.
-It should be a '%s'-sequence.  After inserting an output name
-formatted with this string, an action button is inserted.")
-
-(defvar guix-package-info-obsolete-string "(This package is obsolete)"
-  "String used if a package is obsolete.")
-
-(defun guix-package-info-insert-outputs (outputs entry)
-  "Insert OUTPUTS from package ENTRY at point."
-  (and (guix-entry-value entry 'obsolete)
-       (guix-package-info-insert-obsolete-text))
-  (and (guix-entry-value entry 'non-unique)
-       (guix-entry-value entry 'installed)
-       (guix-package-info-insert-non-unique-text
-        (guix-package-entry->name-specification entry)))
-  (insert "\n")
-  (mapc (lambda (output)
-          (guix-package-info-insert-output output entry))
-        outputs))
-
-(defun guix-package-info-insert-obsolete-text ()
-  "Insert a message about obsolete package at point."
-  (guix-info-insert-indent)
-  (guix-format-insert guix-package-info-obsolete-string
-                      'guix-package-info-obsolete))
-
-(defun guix-package-info-insert-non-unique-text (full-name)
-  "Insert a message about non-unique package with FULL-NAME at point."
-  (insert "\n")
-  (guix-info-insert-indent)
-  (insert "Installed outputs are displayed for a non-unique ")
-  (guix-insert-button full-name 'guix-package-name)
-  (insert " package."))
-
-(defun guix-package-info-insert-output (output entry)
-  "Insert OUTPUT at point.
-Make some fancy text with buttons and additional stuff if the
-current OUTPUT is installed (if there is such output in
-`installed' parameter of a package ENTRY)."
-  (let* ((installed (guix-entry-value entry 'installed))
-         (obsolete  (guix-entry-value entry 'obsolete))
-         (installed-entry (cl-find-if
-                           (lambda (entry)
-                             (string= (guix-entry-value entry 'output)
-                                      output))
-                           installed))
-         (action-type (if installed-entry 'delete 'install)))
-    (guix-info-insert-indent)
-    (guix-format-insert output
-                        (if installed-entry
-                            'guix-package-info-installed-outputs
-                          'guix-package-info-uninstalled-outputs)
-                        guix-package-info-output-format)
-    (guix-package-info-insert-action-button action-type entry output)
-    (when obsolete
-      (guix-info-insert-indent)
-      (guix-package-info-insert-action-button 'upgrade entry output))
-    (insert "\n")
-    (when installed-entry
-      (guix-info-insert-entry installed-entry 'installed-output 2))))
-
-(defun guix-package-info-insert-action-button (type entry output)
-  "Insert button to process an action on a package OUTPUT at point.
-TYPE is one of the following symbols: `install', `delete', `upgrade'.
-ENTRY is an alist with package info."
-  (let ((type-str (capitalize (symbol-name type)))
-        (full-name (guix-package-entry->name-specification entry output)))
-    (guix-info-insert-action-button
-     type-str
-     (lambda (btn)
-       (guix-process-package-actions
-        (guix-ui-current-profile)
-        `((,(button-get btn 'action-type) (,(button-get btn 'id)
-                                           ,(button-get btn 'output))))
-        (current-buffer)))
-     (concat type-str " '" full-name "'")
-     'action-type type
-     'id (or (guix-entry-value entry 'package-id)
-             (guix-entry-id entry))
-     'output output)))
-
-
-;;; Inserting a source
-
-(defface guix-package-info-source
-  '((t :inherit link :underline nil))
-  "Face used for a source URL of a package."
-  :group 'guix-package-info-faces)
-
-(defcustom guix-package-info-auto-find-source nil
-  "If non-nil, find a source file after pressing a \"Show\" button.
-If nil, just display the source file path without finding."
-  :type 'boolean
-  :group 'guix-package-info)
-
-(defcustom guix-package-info-auto-download-source t
-  "If nil, do not automatically download a source file if it doesn't exist.
-After pressing a \"Show\" button, a derivation of the package
-source is calculated and a store file path is displayed.  If this
-variable is non-nil and the source file does not exist in the
-store, it will be automatically downloaded (with a possible
-prompt depending on `guix-operation-confirm' variable)."
-  :type 'boolean
-  :group 'guix-package-info)
-
-(defvar guix-package-info-download-buffer nil
-  "Buffer from which a current download operation was performed.")
-
-(define-button-type 'guix-package-source
-  :supertype 'guix
-  'face 'guix-package-info-source
-  'help-echo ""
-  'action (lambda (_)
-            ;; As a source may not be a real URL (e.g., "mirror://..."),
-            ;; no action is bound to a source button.
-            (message "Yes, this is the source URL. What did you expect?")))
-
-(defun guix-package-info-show-source (entry-id package-id)
-  "Show file name of a package source in the current info buffer.
-Find the file if needed (see `guix-package-info-auto-find-source').
-ENTRY-ID is an ID of the current entry (package or output).
-PACKAGE-ID is an ID of the package which source to show."
-  (let* ((entries (guix-buffer-current-entries))
-         (entry   (guix-entry-by-id entry-id entries))
-         (file    (guix-package-source-path package-id)))
-    (or file
-        (error "Couldn't define file name of the package source"))
-    (let* ((new-entry (cons (cons 'source-file file)
-                            entry))
-           (new-entries (guix-replace-entry entry-id new-entry entries)))
-      (setf (guix-buffer-item-entries guix-buffer-item)
-            new-entries)
-      (guix-buffer-redisplay-goto-button)
-      (if (file-exists-p file)
-          (if guix-package-info-auto-find-source
-              (guix-find-file file)
-            (message "The source store path is displayed."))
-        (if guix-package-info-auto-download-source
-            (guix-package-info-download-source package-id)
-          (message "The source does not exist in the store."))))))
-
-(defun guix-package-info-download-source (package-id)
-  "Download a source of the package PACKAGE-ID."
-  (setq guix-package-info-download-buffer (current-buffer))
-  (guix-package-source-build-derivation
-   package-id
-   "The source does not exist in the store. Download it?"))
-
-(defun guix-package-info-insert-source (source entry)
-  "Insert SOURCE from package ENTRY at point.
-SOURCE is a list of URLs."
-  (if (null source)
-      (guix-format-insert nil)
-    (let* ((source-file (guix-entry-value entry 'source-file))
-           (entry-id    (guix-entry-id entry))
-           (package-id  (or (guix-entry-value entry 'package-id)
-                            entry-id)))
-      (if (null source-file)
-          (guix-info-insert-action-button
-           "Show"
-           (lambda (btn)
-             (guix-package-info-show-source (button-get btn 'entry-id)
-                                            (button-get btn 'package-id)))
-           "Show the source store directory of the current package"
-           'entry-id entry-id
-           'package-id package-id)
-        (unless (file-exists-p source-file)
-          (guix-info-insert-action-button
-           "Download"
-           (lambda (btn)
-             (guix-package-info-download-source
-              (button-get btn 'package-id)))
-           "Download the source into the store"
-           'package-id package-id))
-        (guix-info-insert-value-indent source-file 'guix-file))
-      (guix-info-insert-value-indent source 'guix-package-source))))
-
-(defun guix-package-info-redisplay-after-download ()
-  "Redisplay an 'info' buffer after downloading the package source.
-This function is used to hide a \"Download\" button if needed."
-  (when (buffer-live-p guix-package-info-download-buffer)
-    (with-current-buffer guix-package-info-download-buffer
-      (guix-buffer-redisplay-goto-button))
-    (setq guix-package-info-download-buffer nil)))
-
-(add-hook 'guix-after-source-download-hook
-          'guix-package-info-redisplay-after-download)
-
-
-;;; Displaying outputs
-
-(guix-ui-info-define-interface output
-  :buffer-name "*Guix Package Info*"
-  :format '((name format (format guix-package-info-name))
-            (version format guix-output-info-insert-version)
-            (output format guix-output-info-insert-output)
-            (synopsis simple (indent guix-package-info-synopsis))
-            (source simple guix-package-info-insert-source)
-            (path simple (indent guix-file))
-            (dependencies simple (indent guix-file))
-            (location format (format guix-package-location))
-            (home-url format (format guix-url))
-            (license format (format guix-package-info-license))
-            (inputs format (format guix-package-input))
-            (native-inputs format (format guix-package-native-input))
-            (propagated-inputs format
-                               (format guix-package-propagated-input))
-            (description simple (indent guix-package-info-description)))
-  :titles guix-package-info-titles
-  :required '(id package-id installed non-unique))
-
-(defun guix-output-info-insert-version (version entry)
-  "Insert output VERSION and obsolete text if needed at point."
-  (guix-info-insert-value-format version
-                                 'guix-package-info-version)
-  (and (guix-entry-value entry 'obsolete)
-       (guix-package-info-insert-obsolete-text)))
-
-(defun guix-output-info-insert-output (output entry)
-  "Insert OUTPUT and action buttons at point."
-  (let* ((installed (guix-entry-value entry 'installed))
-         (obsolete  (guix-entry-value entry 'obsolete))
-         (action-type (if installed 'delete 'install)))
-    (guix-info-insert-value-format
-     output
-     (if installed
-         'guix-package-info-installed-outputs
-       'guix-package-info-uninstalled-outputs))
-    (guix-info-insert-indent)
-    (guix-package-info-insert-action-button action-type entry output)
-    (when obsolete
-      (guix-info-insert-indent)
-      (guix-package-info-insert-action-button 'upgrade entry output))))
-
-
-;;; Displaying generations
-
-(guix-ui-info-define-interface generation
-  :buffer-name "*Guix Generation Info*"
-  :format '((number format guix-generation-info-insert-number)
-            (prev-number format (format))
-            (current format guix-generation-info-insert-current)
-            (path simple (indent guix-file))
-            (time format (time)))
-  :titles '((path . "File name")
-            (prev-number . "Previous number")))
-
-(defface guix-generation-info-number
-  '((t :inherit font-lock-keyword-face))
-  "Face used for a number of a generation."
-  :group 'guix-generation-info-faces)
-
-(defface guix-generation-info-current
-  '((t :inherit guix-package-info-installed-outputs))
-  "Face used if a generation is the current one."
-  :group 'guix-generation-info-faces)
-
-(defface guix-generation-info-not-current
-  '((t nil))
-  "Face used if a generation is not the current one."
-  :group 'guix-generation-info-faces)
-
-(defun guix-generation-info-insert-number (number &optional _)
-  "Insert generation NUMBER and action buttons."
-  (guix-info-insert-value-format number 'guix-generation-info-number)
-  (guix-info-insert-indent)
-  (guix-info-insert-action-button
-   "Packages"
-   (lambda (btn)
-     (guix-buffer-get-display-entries
-      'list guix-package-list-type
-      (list (guix-ui-current-profile)
-            'generation (button-get btn 'number))
-      'add))
-   "Show installed packages for this generation"
-   'number number)
-  (guix-info-insert-indent)
-  (guix-info-insert-action-button
-   "Delete"
-   (lambda (btn)
-     (guix-delete-generations (guix-ui-current-profile)
-                              (list (button-get btn 'number))
-                              (current-buffer)))
-   "Delete this generation"
-   'number number))
-
-(defun guix-generation-info-insert-current (val entry)
-  "Insert boolean value VAL showing whether this generation is current."
-  (if val
-      (guix-info-insert-value-format "Yes" 'guix-generation-info-current)
-    (guix-info-insert-value-format "No" 'guix-generation-info-not-current)
-    (guix-info-insert-indent)
-    (guix-info-insert-action-button
-     "Switch"
-     (lambda (btn)
-       (guix-switch-to-generation (guix-ui-current-profile)
-                                  (button-get btn 'number)
-                                  (current-buffer)))
-     "Switch to this generation (make it the current one)"
-     'number (guix-entry-value entry 'number))))
-
-
 (defvar guix-info-font-lock-keywords
   (eval-when-compile
     `((,(rx "(" (group "guix-info-define-interface")
diff --git a/emacs/guix-list.el b/emacs/guix-list.el
index f5c50389ed..719642ad07 100644
--- a/emacs/guix-list.el
+++ b/emacs/guix-list.el
@@ -1,4 +1,4 @@
-;;; guix-list.el --- List buffers for displaying entries   -*- lexical-binding: t -*-
+;;; guix-list.el --- 'List' buffer interface for displaying data  -*- lexical-binding: t -*-
 
 ;; Copyright © 2014, 2015 Alex Kost <alezost@gmail.com>
 
@@ -19,18 +19,17 @@
 
 ;;; Commentary:
 
-;; This file provides a list-like buffer for displaying information
-;; about Guix packages and generations.
+;; This file provides 'list' buffer interface for displaying an arbitrary
+;; data.
 
 ;;; Code:
 
 (require 'cl-lib)
 (require 'tabulated-list)
+(require 'guix-buffer)
 (require 'guix-info)
-(require 'guix-base)
 (require 'guix-entry)
 (require 'guix-utils)
-(require 'guix-ui)
 
 (defgroup guix-list nil
   "General settings for list buffers."
@@ -534,446 +533,6 @@ Set up the current 'list' buffer for displaying '%s' entries."
                    ,@%foreign-args))))))))
 
 
-;;; Displaying packages
-
-(guix-ui-list-define-interface package
-  :buffer-name "*Guix Package List*"
-  :format '((name guix-package-list-get-name 20 t)
-            (version nil 10 nil)
-            (outputs nil 13 t)
-            (installed guix-package-list-get-installed-outputs 13 t)
-            (synopsis guix-list-get-one-line 30 nil))
-  :sort-key '(name)
-  :marks '((install . ?I)
-           (upgrade . ?U)
-           (delete  . ?D)))
-
-(defface guix-package-list-installed
-  '((t :inherit guix-package-info-installed-outputs))
-  "Face used if there are installed outputs for the current package."
-  :group 'guix-package-list-faces)
-
-(defface guix-package-list-obsolete
-  '((t :inherit guix-package-info-obsolete))
-  "Face used if a package is obsolete."
-  :group 'guix-package-list-faces)
-
-(defcustom guix-package-list-generation-marking-enabled nil
-  "If non-nil, allow putting marks in a list with 'generation packages'.
-
-By default this is disabled, because it may be confusing.  For
-example a package is installed in some generation, so a user can
-mark it for deletion in the list of packages from this
-generation, but the package may not be installed in the latest
-generation, so actually it cannot be deleted.
-
-If you managed to understand the explanation above or if you
-really know what you do or if you just don't care, you can set
-this variable to t.  It should not do much harm anyway (most
-likely)."
-  :type 'boolean
-  :group 'guix-package-list)
-
-(let ((map guix-package-list-mode-map))
-  (define-key map (kbd "e")   'guix-package-list-edit)
-  (define-key map (kbd "x")   'guix-package-list-execute)
-  (define-key map (kbd "i")   'guix-package-list-mark-install)
-  (define-key map (kbd "d")   'guix-package-list-mark-delete)
-  (define-key map (kbd "U")   'guix-package-list-mark-upgrade)
-  (define-key map (kbd "^")   'guix-package-list-mark-upgrades))
-
-(defun guix-package-list-get-name (name entry)
-  "Return NAME of the package ENTRY.
-Colorize it with `guix-package-list-installed' or
-`guix-package-list-obsolete' if needed."
-  (guix-get-string name
-                   (cond ((guix-entry-value entry 'obsolete)
-                          'guix-package-list-obsolete)
-                         ((guix-entry-value entry 'installed)
-                          'guix-package-list-installed))))
-
-(defun guix-package-list-get-installed-outputs (installed &optional _)
-  "Return string with outputs from INSTALLED entries."
-  (guix-get-string
-   (mapcar (lambda (entry)
-             (guix-entry-value entry 'output))
-           installed)))
-
-(defun guix-package-list-marking-check ()
-  "Signal an error if marking is disabled for the current buffer."
-  (when (and (not guix-package-list-generation-marking-enabled)
-             (or (derived-mode-p 'guix-package-list-mode)
-                 (derived-mode-p 'guix-output-list-mode))
-             (eq (guix-ui-current-search-type) 'generation))
-    (error "Action marks are disabled for lists of 'generation packages'")))
-
-(defun guix-package-list-mark-outputs (mark default
-                                       &optional prompt available)
-  "Mark the current package with MARK and move to the next line.
-If PROMPT is non-nil, use it to ask a user for outputs from
-AVAILABLE list, otherwise mark all DEFAULT outputs."
-  (let ((outputs (if prompt
-                     (guix-completing-read-multiple
-                      prompt available nil t)
-                   default)))
-    (apply #'guix-list--mark mark t outputs)))
-
-(defun guix-package-list-mark-install (&optional arg)
-  "Mark the current package for installation and move to the next line.
-With ARG, prompt for the outputs to install (several outputs may
-be separated with \",\")."
-  (interactive "P")
-  (guix-package-list-marking-check)
-  (let* ((entry     (guix-list-current-entry))
-         (all       (guix-entry-value entry 'outputs))
-         (installed (guix-package-installed-outputs entry))
-         (available (cl-set-difference all installed :test #'string=)))
-    (or available
-        (user-error "This package is already installed"))
-    (guix-package-list-mark-outputs
-     'install '("out")
-     (and arg "Output(s) to install: ")
-     available)))
-
-(defun guix-package-list-mark-delete (&optional arg)
-  "Mark the current package for deletion and move to the next line.
-With ARG, prompt for the outputs to delete (several outputs may
-be separated with \",\")."
-  (interactive "P")
-  (guix-package-list-marking-check)
-  (let* ((entry (guix-list-current-entry))
-         (installed (guix-package-installed-outputs entry)))
-    (or installed
-        (user-error "This package is not installed"))
-    (guix-package-list-mark-outputs
-     'delete installed
-     (and arg "Output(s) to delete: ")
-     installed)))
-
-(defun guix-package-list-mark-upgrade (&optional arg)
-  "Mark the current package for upgrading and move to the next line.
-With ARG, prompt for the outputs to upgrade (several outputs may
-be separated with \",\")."
-  (interactive "P")
-  (guix-package-list-marking-check)
-  (let* ((entry (guix-list-current-entry))
-         (installed (guix-package-installed-outputs entry)))
-    (or installed
-        (user-error "This package is not installed"))
-    (when (or (guix-entry-value entry 'obsolete)
-              (y-or-n-p "This package is not obsolete.  Try to upgrade it anyway? "))
-      (guix-package-list-mark-outputs
-       'upgrade installed
-       (and arg "Output(s) to upgrade: ")
-       installed))))
-
-(defun guix-list-mark-package-upgrades (fun)
-  "Mark all obsolete packages for upgrading.
-Use FUN to perform marking of the current line.  FUN should
-accept an entry as argument."
-  (guix-package-list-marking-check)
-  (let ((obsolete (cl-remove-if-not
-                   (lambda (entry)
-                     (guix-entry-value entry 'obsolete))
-                   (guix-buffer-current-entries))))
-    (guix-list-for-each-line
-     (lambda ()
-       (let* ((id (guix-list-current-id))
-              (entry (cl-find-if
-                      (lambda (entry)
-                        (equal id (guix-entry-id entry)))
-                      obsolete)))
-         (when entry
-           (funcall fun entry)))))))
-
-(defun guix-package-list-mark-upgrades ()
-  "Mark all obsolete packages for upgrading."
-  (interactive)
-  (guix-list-mark-package-upgrades
-   (lambda (entry)
-     (apply #'guix-list--mark
-            'upgrade nil
-            (guix-package-installed-outputs entry)))))
-
-(defun guix-list-execute-package-actions (fun)
-  "Perform actions on the marked packages.
-Use FUN to define actions suitable for `guix-process-package-actions'.
-FUN should accept action-type as argument."
-  (let ((actions (delq nil
-                       (mapcar fun '(install delete upgrade)))))
-    (if actions
-        (guix-process-package-actions (guix-ui-current-profile)
-                                      actions (current-buffer))
-      (user-error "No operations specified"))))
-
-(defun guix-package-list-execute ()
-  "Perform actions on the marked packages."
-  (interactive)
-  (guix-list-execute-package-actions #'guix-package-list-make-action))
-
-(defun guix-package-list-make-action (action-type)
-  "Return action specification for the packages marked with ACTION-TYPE.
-Return nil, if there are no packages marked with ACTION-TYPE.
-The specification is suitable for `guix-process-package-actions'."
-  (let ((specs (guix-list-get-marked-args action-type)))
-    (and specs (cons action-type specs))))
-
-(defun guix-package-list-edit ()
-  "Go to the location of the current package."
-  (interactive)
-  (guix-edit (guix-list-current-id)))
-
-
-;;; Displaying outputs
-
-(guix-ui-list-define-interface output
-  :buffer-name "*Guix Package List*"
-  :describe-function 'guix-output-list-describe
-  :format '((name guix-package-list-get-name 20 t)
-            (version nil 10 nil)
-            (output nil 9 t)
-            (installed nil 12 t)
-            (synopsis guix-list-get-one-line 30 nil))
-  :required '(id package-id)
-  :sort-key '(name)
-  :marks '((install . ?I)
-           (upgrade . ?U)
-           (delete  . ?D)))
-
-(let ((map guix-output-list-mode-map))
-  (define-key map (kbd "e")   'guix-output-list-edit)
-  (define-key map (kbd "x")   'guix-output-list-execute)
-  (define-key map (kbd "i")   'guix-output-list-mark-install)
-  (define-key map (kbd "d")   'guix-output-list-mark-delete)
-  (define-key map (kbd "U")   'guix-output-list-mark-upgrade)
-  (define-key map (kbd "^")   'guix-output-list-mark-upgrades))
-
-(defun guix-output-list-mark-install ()
-  "Mark the current output for installation and move to the next line."
-  (interactive)
-  (guix-package-list-marking-check)
-  (let* ((entry     (guix-list-current-entry))
-         (installed (guix-entry-value entry 'installed)))
-    (if installed
-        (user-error "This output is already installed")
-      (guix-list--mark 'install t))))
-
-(defun guix-output-list-mark-delete ()
-  "Mark the current output for deletion and move to the next line."
-  (interactive)
-  (guix-package-list-marking-check)
-  (let* ((entry     (guix-list-current-entry))
-         (installed (guix-entry-value entry 'installed)))
-    (if installed
-        (guix-list--mark 'delete t)
-      (user-error "This output is not installed"))))
-
-(defun guix-output-list-mark-upgrade ()
-  "Mark the current output for deletion and move to the next line."
-  (interactive)
-  (guix-package-list-marking-check)
-  (let* ((entry     (guix-list-current-entry))
-         (installed (guix-entry-value entry 'installed)))
-    (or installed
-        (user-error "This output is not installed"))
-    (when (or (guix-entry-value entry 'obsolete)
-              (y-or-n-p "This output is not obsolete.  Try to upgrade it anyway? "))
-      (guix-list--mark 'upgrade t))))
-
-(defun guix-output-list-mark-upgrades ()
-  "Mark all obsolete package outputs for upgrading."
-  (interactive)
-  (guix-list-mark-package-upgrades
-   (lambda (_) (guix-list--mark 'upgrade))))
-
-(defun guix-output-list-execute ()
-  "Perform actions on the marked outputs."
-  (interactive)
-  (guix-list-execute-package-actions #'guix-output-list-make-action))
-
-(defun guix-output-list-make-action (action-type)
-  "Return action specification for the outputs marked with ACTION-TYPE.
-Return nil, if there are no outputs marked with ACTION-TYPE.
-The specification is suitable for `guix-process-output-actions'."
-  (let ((ids (guix-list-get-marked-id-list action-type)))
-    (and ids (cons action-type
-                   (mapcar #'guix-package-id-and-output-by-output-id
-                           ids)))))
-
-(defun guix-output-list-describe (ids)
-  "Describe outputs with IDS (list of output identifiers).
-See `guix-package-info-type'."
-  (if (eq guix-package-info-type 'output)
-      (guix-buffer-get-display-entries
-       'info 'output
-       (cl-list* (guix-ui-current-profile) 'id ids)
-       'add)
-    (let ((pids (mapcar (lambda (oid)
-                          (car (guix-package-id-and-output-by-output-id
-                                oid)))
-                        ids)))
-      (guix-buffer-get-display-entries
-       'info 'package
-       (cl-list* (guix-ui-current-profile)
-                 'id (cl-remove-duplicates pids))
-       'add))))
-
-(defun guix-output-list-edit ()
-  "Go to the location of the current package."
-  (interactive)
-  (guix-edit (guix-entry-value (guix-list-current-entry)
-                               'package-id)))
-
-
-;;; Displaying generations
-
-(guix-ui-list-define-interface generation
-  :buffer-name "*Guix Generation List*"
-  :format '((number nil 5 guix-list-sort-numerically-0 :right-align t)
-            (current guix-generation-list-get-current 10 t)
-            (time guix-list-get-time 20 t)
-            (path guix-list-get-file-path 30 t))
-  :titles '((number . "N."))
-  :sort-key '(number . t)
-  :marks '((delete . ?D)))
-
-(let ((map guix-generation-list-mode-map))
-  (define-key map (kbd "RET") 'guix-generation-list-show-packages)
-  (define-key map (kbd "+")   'guix-generation-list-show-added-packages)
-  (define-key map (kbd "-")   'guix-generation-list-show-removed-packages)
-  (define-key map (kbd "=")   'guix-generation-list-diff)
-  (define-key map (kbd "D")   'guix-generation-list-diff)
-  (define-key map (kbd "e")   'guix-generation-list-ediff)
-  (define-key map (kbd "x")   'guix-generation-list-execute)
-  (define-key map (kbd "s")   'guix-generation-list-switch)
-  (define-key map (kbd "d")   'guix-generation-list-mark-delete))
-
-(defun guix-generation-list-get-current (val &optional _)
-  "Return string from VAL showing whether this generation is current.
-VAL is a boolean value."
-  (if val "(current)" ""))
-
-(defun guix-generation-list-switch ()
-  "Switch current profile to the generation at point."
-  (interactive)
-  (let* ((entry   (guix-list-current-entry))
-         (current (guix-entry-value entry 'current))
-         (number  (guix-entry-value entry 'number)))
-    (if current
-        (user-error "This generation is already the current one")
-      (guix-switch-to-generation (guix-ui-current-profile)
-                                 number (current-buffer)))))
-
-(defun guix-generation-list-show-packages ()
-  "List installed packages for the generation at point."
-  (interactive)
-  (guix-get-show-packages
-   (guix-ui-current-profile)
-   'generation (guix-list-current-id)))
-
-(defun guix-generation-list-generations-to-compare ()
-  "Return a sorted list of 2 marked generations for comparing."
-  (let ((numbers (guix-list-get-marked-id-list 'general)))
-    (if (/= (length numbers) 2)
-        (user-error "2 generations should be marked for comparing")
-      (sort numbers #'<))))
-
-(defun guix-generation-list-show-added-packages ()
-  "List package outputs added to the latest marked generation.
-If 2 generations are marked with \\[guix-list-mark], display
-outputs installed in the latest marked generation that were not
-installed in the other one."
-  (interactive)
-  (guix-buffer-get-display-entries
-   'list 'output
-   (cl-list* (guix-ui-current-profile)
-             'generation-diff
-             (reverse (guix-generation-list-generations-to-compare)))
-   'add))
-
-(defun guix-generation-list-show-removed-packages ()
-  "List package outputs removed from the latest marked generation.
-If 2 generations are marked with \\[guix-list-mark], display
-outputs not installed in the latest marked generation that were
-installed in the other one."
-  (interactive)
-  (guix-buffer-get-display-entries
-   'list 'output
-   (cl-list* (guix-ui-current-profile)
-             'generation-diff
-             (guix-generation-list-generations-to-compare))
-   'add))
-
-(defun guix-generation-list-compare (diff-fun gen-fun)
-  "Run GEN-FUN on the 2 marked generations and run DIFF-FUN on the results."
-  (cl-multiple-value-bind (gen1 gen2)
-      (guix-generation-list-generations-to-compare)
-    (funcall diff-fun
-             (funcall gen-fun gen1)
-             (funcall gen-fun gen2))))
-
-(defun guix-generation-list-ediff-manifests ()
-  "Run Ediff on manifests of the 2 marked generations."
-  (interactive)
-  (guix-generation-list-compare
-   #'ediff-files
-   #'guix-profile-generation-manifest-file))
-
-(defun guix-generation-list-diff-manifests ()
-  "Run Diff on manifests of the 2 marked generations."
-  (interactive)
-  (guix-generation-list-compare
-   #'guix-diff
-   #'guix-profile-generation-manifest-file))
-
-(defun guix-generation-list-ediff-packages ()
-  "Run Ediff on package outputs installed in the 2 marked generations."
-  (interactive)
-  (guix-generation-list-compare
-   #'ediff-buffers
-   #'guix-profile-generation-packages-buffer))
-
-(defun guix-generation-list-diff-packages ()
-  "Run Diff on package outputs installed in the 2 marked generations."
-  (interactive)
-  (guix-generation-list-compare
-   #'guix-diff
-   #'guix-profile-generation-packages-buffer))
-
-(defun guix-generation-list-ediff (arg)
-  "Run Ediff on package outputs installed in the 2 marked generations.
-With ARG, run Ediff on manifests of the marked generations."
-  (interactive "P")
-  (if arg
-      (guix-generation-list-ediff-manifests)
-    (guix-generation-list-ediff-packages)))
-
-(defun guix-generation-list-diff (arg)
-  "Run Diff on package outputs installed in the 2 marked generations.
-With ARG, run Diff on manifests of the marked generations."
-  (interactive "P")
-  (if arg
-      (guix-generation-list-diff-manifests)
-    (guix-generation-list-diff-packages)))
-
-(defun guix-generation-list-mark-delete (&optional arg)
-  "Mark the current generation for deletion and move to the next line.
-With ARG, mark all generations for deletion."
-  (interactive "P")
-  (if arg
-      (guix-list-mark-all 'delete)
-    (guix-list--mark 'delete t)))
-
-(defun guix-generation-list-execute ()
-  "Delete marked generations."
-  (interactive)
-  (let ((marked (guix-list-get-marked-id-list 'delete)))
-    (or marked
-        (user-error "No generations marked for deletion"))
-    (guix-delete-generations (guix-ui-current-profile)
-                             marked (current-buffer))))
-
-
 (defvar guix-list-font-lock-keywords
   (eval-when-compile
     `((,(rx "(" (group "guix-list-define-interface")
diff --git a/emacs/guix-ui-generation.el b/emacs/guix-ui-generation.el
new file mode 100644
index 0000000000..7d6762a444
--- /dev/null
+++ b/emacs/guix-ui-generation.el
@@ -0,0 +1,439 @@
+;;; guix-ui-generation.el --- Interface for displaying generations  -*- lexical-binding: t -*-
+
+;; Copyright © 2014, 2015 Alex Kost <alezost@gmail.com>
+
+;; This file is part of GNU Guix.
+
+;; GNU Guix is free software; you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; GNU Guix is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; This file provides an interface for displaying profile generations in
+;; 'list' and 'info' buffers, and commands for working with them.
+
+;;; Code:
+
+(require 'cl-lib)
+(require 'guix-buffer)
+(require 'guix-list)
+(require 'guix-info)
+(require 'guix-ui)
+(require 'guix-ui-package)
+(require 'guix-base)
+(require 'guix-backend)
+(require 'guix-guile)
+(require 'guix-entry)
+(require 'guix-utils)
+
+(defgroup guix-generation nil
+  "Interface for displaying generations."
+  :group 'guix-ui)
+
+(defun guix-generation-get-display (profile search-type &rest search-values)
+  "Search for generations and show results.
+
+If PROFILE is nil, use `guix-current-profile'.
+
+See `guix-ui-get-entries' for the meaning of SEARCH-TYPE and
+SEARCH-VALUES."
+  (let ((args (cl-list* (or profile guix-current-profile)
+                        search-type search-values)))
+    (guix-buffer-get-display-entries
+     'list 'generation args 'add)))
+
+(defun guix-delete-generations (profile generations
+                                &optional operation-buffer)
+  "Delete GENERATIONS from PROFILE.
+Each element from GENERATIONS is a generation number."
+  (when (or (not guix-operation-confirm)
+            (y-or-n-p
+             (let ((count (length generations)))
+               (if (> count 1)
+                   (format "Delete %d generations from profile '%s'? "
+                           count profile)
+                 (format "Delete generation %d from profile '%s'? "
+                         (car generations) profile)))))
+    (guix-eval-in-repl
+     (guix-make-guile-expression
+      'delete-generations* profile generations)
+     operation-buffer)))
+
+(defun guix-switch-to-generation (profile generation
+                                  &optional operation-buffer)
+  "Switch PROFILE to GENERATION."
+  (when (or (not guix-operation-confirm)
+            (y-or-n-p (format "Switch profile '%s' to generation %d? "
+                              profile generation)))
+    (guix-eval-in-repl
+     (guix-make-guile-expression
+      'switch-to-generation* profile generation)
+     operation-buffer)))
+
+
+;;; Generation 'info'
+
+(guix-ui-info-define-interface generation
+  :buffer-name "*Guix Generation Info*"
+  :format '((number format guix-generation-info-insert-number)
+            (prev-number format (format))
+            (current format guix-generation-info-insert-current)
+            (path simple (indent guix-file))
+            (time format (time)))
+  :titles '((path . "File name")
+            (prev-number . "Previous number")))
+
+(defface guix-generation-info-number
+  '((t :inherit font-lock-keyword-face))
+  "Face used for a number of a generation."
+  :group 'guix-generation-info-faces)
+
+(defface guix-generation-info-current
+  '((t :inherit guix-package-info-installed-outputs))
+  "Face used if a generation is the current one."
+  :group 'guix-generation-info-faces)
+
+(defface guix-generation-info-not-current
+  '((t nil))
+  "Face used if a generation is not the current one."
+  :group 'guix-generation-info-faces)
+
+(defun guix-generation-info-insert-number (number &optional _)
+  "Insert generation NUMBER and action buttons."
+  (guix-info-insert-value-format number 'guix-generation-info-number)
+  (guix-info-insert-indent)
+  (guix-info-insert-action-button
+   "Packages"
+   (lambda (btn)
+     (guix-buffer-get-display-entries
+      'list guix-package-list-type
+      (list (guix-ui-current-profile)
+            'generation (button-get btn 'number))
+      'add))
+   "Show installed packages for this generation"
+   'number number)
+  (guix-info-insert-indent)
+  (guix-info-insert-action-button
+   "Delete"
+   (lambda (btn)
+     (guix-delete-generations (guix-ui-current-profile)
+                              (list (button-get btn 'number))
+                              (current-buffer)))
+   "Delete this generation"
+   'number number))
+
+(defun guix-generation-info-insert-current (val entry)
+  "Insert boolean value VAL showing whether this generation is current."
+  (if val
+      (guix-info-insert-value-format "Yes" 'guix-generation-info-current)
+    (guix-info-insert-value-format "No" 'guix-generation-info-not-current)
+    (guix-info-insert-indent)
+    (guix-info-insert-action-button
+     "Switch"
+     (lambda (btn)
+       (guix-switch-to-generation (guix-ui-current-profile)
+                                  (button-get btn 'number)
+                                  (current-buffer)))
+     "Switch to this generation (make it the current one)"
+     'number (guix-entry-value entry 'number))))
+
+
+;;; Generation 'list'
+
+(guix-ui-list-define-interface generation
+  :buffer-name "*Guix Generation List*"
+  :format '((number nil 5 guix-list-sort-numerically-0 :right-align t)
+            (current guix-generation-list-get-current 10 t)
+            (time guix-list-get-time 20 t)
+            (path guix-list-get-file-path 30 t))
+  :titles '((number . "N."))
+  :sort-key '(number . t)
+  :marks '((delete . ?D)))
+
+(let ((map guix-generation-list-mode-map))
+  (define-key map (kbd "RET") 'guix-generation-list-show-packages)
+  (define-key map (kbd "+")   'guix-generation-list-show-added-packages)
+  (define-key map (kbd "-")   'guix-generation-list-show-removed-packages)
+  (define-key map (kbd "=")   'guix-generation-list-diff)
+  (define-key map (kbd "D")   'guix-generation-list-diff)
+  (define-key map (kbd "e")   'guix-generation-list-ediff)
+  (define-key map (kbd "x")   'guix-generation-list-execute)
+  (define-key map (kbd "s")   'guix-generation-list-switch)
+  (define-key map (kbd "c")   'guix-generation-list-switch)
+  (define-key map (kbd "d")   'guix-generation-list-mark-delete))
+
+(defun guix-generation-list-get-current (val &optional _)
+  "Return string from VAL showing whether this generation is current.
+VAL is a boolean value."
+  (if val "(current)" ""))
+
+(defun guix-generation-list-switch ()
+  "Switch current profile to the generation at point."
+  (interactive)
+  (let* ((entry   (guix-list-current-entry))
+         (current (guix-entry-value entry 'current))
+         (number  (guix-entry-value entry 'number)))
+    (if current
+        (user-error "This generation is already the current one")
+      (guix-switch-to-generation (guix-ui-current-profile)
+                                 number (current-buffer)))))
+
+(defun guix-generation-list-show-packages ()
+  "List installed packages for the generation at point."
+  (interactive)
+  (guix-package-get-display
+   (guix-ui-current-profile)
+   'generation (guix-list-current-id)))
+
+(defun guix-generation-list-generations-to-compare ()
+  "Return a sorted list of 2 marked generations for comparing."
+  (let ((numbers (guix-list-get-marked-id-list 'general)))
+    (if (/= (length numbers) 2)
+        (user-error "2 generations should be marked for comparing")
+      (sort numbers #'<))))
+
+(defun guix-generation-list-show-added-packages ()
+  "List package outputs added to the latest marked generation.
+If 2 generations are marked with \\[guix-list-mark], display
+outputs installed in the latest marked generation that were not
+installed in the other one."
+  (interactive)
+  (guix-buffer-get-display-entries
+   'list 'output
+   (cl-list* (guix-ui-current-profile)
+             'generation-diff
+             (reverse (guix-generation-list-generations-to-compare)))
+   'add))
+
+(defun guix-generation-list-show-removed-packages ()
+  "List package outputs removed from the latest marked generation.
+If 2 generations are marked with \\[guix-list-mark], display
+outputs not installed in the latest marked generation that were
+installed in the other one."
+  (interactive)
+  (guix-buffer-get-display-entries
+   'list 'output
+   (cl-list* (guix-ui-current-profile)
+             'generation-diff
+             (guix-generation-list-generations-to-compare))
+   'add))
+
+(defun guix-generation-list-compare (diff-fun gen-fun)
+  "Run GEN-FUN on the 2 marked generations and run DIFF-FUN on the results."
+  (cl-multiple-value-bind (gen1 gen2)
+      (guix-generation-list-generations-to-compare)
+    (funcall diff-fun
+             (funcall gen-fun gen1)
+             (funcall gen-fun gen2))))
+
+(defun guix-generation-list-ediff-manifests ()
+  "Run Ediff on manifests of the 2 marked generations."
+  (interactive)
+  (guix-generation-list-compare
+   #'ediff-files
+   #'guix-profile-generation-manifest-file))
+
+(defun guix-generation-list-diff-manifests ()
+  "Run Diff on manifests of the 2 marked generations."
+  (interactive)
+  (guix-generation-list-compare
+   #'guix-diff
+   #'guix-profile-generation-manifest-file))
+
+(defun guix-generation-list-ediff-packages ()
+  "Run Ediff on package outputs installed in the 2 marked generations."
+  (interactive)
+  (guix-generation-list-compare
+   #'ediff-buffers
+   #'guix-profile-generation-packages-buffer))
+
+(defun guix-generation-list-diff-packages ()
+  "Run Diff on package outputs installed in the 2 marked generations."
+  (interactive)
+  (guix-generation-list-compare
+   #'guix-diff
+   #'guix-profile-generation-packages-buffer))
+
+(defun guix-generation-list-ediff (arg)
+  "Run Ediff on package outputs installed in the 2 marked generations.
+With ARG, run Ediff on manifests of the marked generations."
+  (interactive "P")
+  (if arg
+      (guix-generation-list-ediff-manifests)
+    (guix-generation-list-ediff-packages)))
+
+(defun guix-generation-list-diff (arg)
+  "Run Diff on package outputs installed in the 2 marked generations.
+With ARG, run Diff on manifests of the marked generations."
+  (interactive "P")
+  (if arg
+      (guix-generation-list-diff-manifests)
+    (guix-generation-list-diff-packages)))
+
+(defun guix-generation-list-mark-delete (&optional arg)
+  "Mark the current generation for deletion and move to the next line.
+With ARG, mark all generations for deletion."
+  (interactive "P")
+  (if arg
+      (guix-list-mark-all 'delete)
+    (guix-list--mark 'delete t)))
+
+(defun guix-generation-list-execute ()
+  "Delete marked generations."
+  (interactive)
+  (let ((marked (guix-list-get-marked-id-list 'delete)))
+    (or marked
+        (user-error "No generations marked for deletion"))
+    (guix-delete-generations (guix-ui-current-profile)
+                             marked (current-buffer))))
+
+
+;;; Inserting packages to compare generations
+
+(defcustom guix-generation-packages-buffer-name-function
+  #'guix-generation-packages-buffer-name-default
+  "Function used to define name of a buffer with generation packages.
+This function is called with 2 arguments: PROFILE (string) and
+GENERATION (number)."
+  :type '(choice (function-item guix-generation-packages-buffer-name-default)
+                 (function-item guix-generation-packages-buffer-name-long)
+                 (function :tag "Other function"))
+  :group 'guix-generation)
+
+(defcustom guix-generation-packages-update-buffer t
+  "If non-nil, always update list of packages during comparing generations.
+If nil, generation packages are received only once.  So when you
+compare generation 1 and generation 2, the packages for both
+generations will be received.  Then if you compare generation 1
+and generation 3, only the packages for generation 3 will be
+received.  Thus if you use comparing of different generations a
+lot, you may set this variable to nil to improve the
+performance."
+  :type 'boolean
+  :group 'guix-generation)
+
+(defvar guix-generation-output-name-width 30
+  "Width of an output name \"column\".
+This variable is used in auxiliary buffers for comparing generations.")
+
+(defun guix-generation-packages (profile generation)
+  "Return a list of sorted packages installed in PROFILE's GENERATION.
+Each element of the list is a list of the package specification
+and its store path."
+  (let ((names+paths (guix-eval-read
+                      (guix-make-guile-expression
+                       'generation-package-specifications+paths
+                       profile generation))))
+    (sort names+paths
+          (lambda (a b)
+            (string< (car a) (car b))))))
+
+(defun guix-generation-packages-buffer-name-default (profile generation)
+  "Return name of a buffer for displaying GENERATION's package outputs.
+Use base name of PROFILE file name."
+  (let ((profile-name (file-name-base (directory-file-name profile))))
+    (format "*Guix %s: generation %s*"
+            profile-name generation)))
+
+(defun guix-generation-packages-buffer-name-long (profile generation)
+  "Return name of a buffer for displaying GENERATION's package outputs.
+Use the full PROFILE file name."
+  (format "*Guix generation %s (%s)*"
+          generation profile))
+
+(defun guix-generation-packages-buffer-name (profile generation)
+  "Return name of a buffer for displaying GENERATION's package outputs."
+  (funcall guix-generation-packages-buffer-name-function
+           profile generation))
+
+(defun guix-generation-insert-package (name path)
+  "Insert package output NAME and store PATH at point."
+  (insert name)
+  (indent-to guix-generation-output-name-width 2)
+  (insert path "\n"))
+
+(defun guix-generation-insert-packages (buffer profile generation)
+  "Insert package outputs installed in PROFILE's GENERATION in BUFFER."
+  (with-current-buffer buffer
+    (setq buffer-read-only nil
+          indent-tabs-mode nil)
+    (erase-buffer)
+    (mapc (lambda (name+path)
+            (guix-generation-insert-package
+             (car name+path) (cadr name+path)))
+          (guix-generation-packages profile generation))))
+
+(defun guix-generation-packages-buffer (profile generation)
+  "Return buffer with package outputs installed in PROFILE's GENERATION.
+Create the buffer if needed."
+  (let ((buf-name (guix-generation-packages-buffer-name
+                   profile generation)))
+    (or (and (null guix-generation-packages-update-buffer)
+             (get-buffer buf-name))
+        (let ((buf (get-buffer-create buf-name)))
+          (guix-generation-insert-packages buf profile generation)
+          buf))))
+
+(defun guix-profile-generation-manifest-file (generation)
+  "Return the file name of a GENERATION's manifest.
+GENERATION is a generation number of the current profile."
+  (guix-manifest-file (guix-ui-current-profile) generation))
+
+(defun guix-profile-generation-packages-buffer (generation)
+  "Insert GENERATION's package outputs in a buffer and return it.
+GENERATION is a generation number of the current profile."
+  (guix-generation-packages-buffer (guix-ui-current-profile)
+                                   generation))
+
+
+;;; Interactive commands
+
+;;;###autoload
+(defun guix-generations (&optional profile)
+  "Display information about all generations.
+If PROFILE is nil, use `guix-current-profile'.
+Interactively with prefix, prompt for PROFILE."
+  (interactive
+   (list (and current-prefix-arg
+              (guix-profile-prompt))))
+  (guix-generation-get-display profile 'all))
+
+;;;###autoload
+(defun guix-last-generations (number &optional profile)
+  "Display information about last NUMBER generations.
+If PROFILE is nil, use `guix-current-profile'.
+Interactively with prefix, prompt for PROFILE."
+  (interactive
+   (list (read-number "The number of last generations: ")
+         (and current-prefix-arg
+              (guix-profile-prompt))))
+  (guix-generation-get-display profile 'last number))
+
+;;;###autoload
+(defun guix-generations-by-time (from to &optional profile)
+  "Display information about generations created between FROM and TO.
+FROM and TO should be time values.
+If PROFILE is nil, use `guix-current-profile'.
+Interactively with prefix, prompt for PROFILE."
+  (interactive
+   (list (guix-read-date "Find generations (from): ")
+         (guix-read-date "Find generations (to): ")
+         (and current-prefix-arg
+              (guix-profile-prompt))))
+  (guix-generation-get-display profile 'time
+                               (float-time from)
+                               (float-time to)))
+
+(provide 'guix-ui-generation)
+
+;;; guix-ui-generation.el ends here
diff --git a/emacs/guix-ui-package.el b/emacs/guix-ui-package.el
new file mode 100644
index 0000000000..299822aae9
--- /dev/null
+++ b/emacs/guix-ui-package.el
@@ -0,0 +1,958 @@
+;;; guix-ui-package.el --- Interface for displaying packages  -*- lexical-binding: t -*-
+
+;; Copyright © 2014, 2015 Alex Kost <alezost@gmail.com>
+
+;; This file is part of GNU Guix.
+
+;; GNU Guix is free software; you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; GNU Guix is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; This file provides an interface for displaying packages and outputs
+;; in 'list' and 'info' buffers, and commands for working with them.
+
+;;; Code:
+
+(require 'cl-lib)
+(require 'guix-buffer)
+(require 'guix-list)
+(require 'guix-info)
+(require 'guix-ui)
+(require 'guix-base)
+(require 'guix-backend)
+(require 'guix-guile)
+(require 'guix-entry)
+(require 'guix-utils)
+
+(defgroup guix-package nil
+  "Interface for displaying packages and outputs."
+  :group 'guix-ui)
+
+(defcustom guix-package-list-type 'output
+  "Define how to display packages in 'list' buffer.
+Should be a symbol `package' or `output' (if `output', display each
+output on a separate line; if `package', display each package on
+a separate line)."
+  :type '(choice (const :tag "List of packages" package)
+                 (const :tag "List of outputs" output))
+  :group 'guix-package)
+
+(defcustom guix-package-info-type 'package
+  "Define how to display packages in 'info' buffer.
+Should be a symbol `package' or `output' (if `output', display
+each output separately; if `package', display outputs inside
+package data)."
+  :type '(choice (const :tag "Display packages" package)
+                 (const :tag "Display outputs" output))
+  :group 'guix-package)
+
+(defcustom guix-package-list-single nil
+  "If non-nil, list a package even if it is the only matching result.
+If nil, show a single package in the info buffer."
+  :type 'boolean
+  :group 'guix)
+
+(defun guix-package-get-display (profile search-type &rest search-values)
+  "Search for packages/outputs and show results.
+
+If PROFILE is nil, use `guix-current-profile'.
+
+See `guix-ui-get-entries' for the meaning of SEARCH-TYPE and
+SEARCH-VALUES.
+
+Results are displayed in the list buffer, unless a single package
+is found and `guix-package-list-single' is nil."
+  (let* ((args    (cl-list* (or profile guix-current-profile)
+                            search-type search-values))
+         (entries (guix-buffer-get-entries
+                   'list guix-package-list-type args)))
+    (if (or guix-package-list-single
+            (null entries)
+            (cdr entries))
+        (guix-buffer-display-entries
+         entries 'list guix-package-list-type args 'add)
+      (guix-buffer-get-display-entries
+       'info guix-package-info-type args 'add))))
+
+(defun guix-package-entry->name-specification (entry &optional output)
+  "Return name specification of the package ENTRY and OUTPUT."
+  (guix-package-name-specification
+   (guix-entry-value entry 'name)
+   (guix-entry-value entry 'version)
+   (or output (guix-entry-value entry 'output))))
+
+(defun guix-package-entries->name-specifications (entries)
+  "Return name specifications by the package or output ENTRIES."
+  (cl-remove-duplicates (mapcar #'guix-package-entry->name-specification
+                                entries)
+                        :test #'string=))
+
+(defun guix-package-installed-outputs (entry)
+  "Return a list of installed outputs for the package ENTRY."
+  (mapcar (lambda (installed-entry)
+            (guix-entry-value installed-entry 'output))
+          (guix-entry-value entry 'installed)))
+
+(defun guix-package-id-and-output-by-output-id (output-id)
+  "Return a list (PACKAGE-ID OUTPUT) by OUTPUT-ID."
+  (cl-multiple-value-bind (package-id-str output)
+      (split-string output-id ":")
+    (let ((package-id (string-to-number package-id-str)))
+      (list (if (= 0 package-id) package-id-str package-id)
+            output))))
+
+
+;;; Processing package actions
+
+(defun guix-process-package-actions (profile actions
+                                     &optional operation-buffer)
+  "Process package ACTIONS on PROFILE.
+Each action is a list of the form:
+
+  (ACTION-TYPE PACKAGE-SPEC ...)
+
+ACTION-TYPE is one of the following symbols: `install',
+`upgrade', `remove'/`delete'.
+PACKAGE-SPEC should have the following form: (ID [OUTPUT] ...)."
+  (let (install upgrade remove)
+    (mapc (lambda (action)
+            (let ((action-type (car action))
+                  (specs (cdr action)))
+              (cl-case action-type
+                (install (setq install (append install specs)))
+                (upgrade (setq upgrade (append upgrade specs)))
+                ((remove delete) (setq remove (append remove specs))))))
+          actions)
+    (when (guix-continue-package-operation-p
+           profile
+           :install install :upgrade upgrade :remove remove)
+      (guix-eval-in-repl
+       (guix-make-guile-expression
+        'process-package-actions profile
+        :install install :upgrade upgrade :remove remove
+        :use-substitutes? (or guix-use-substitutes 'f)
+        :dry-run? (or guix-dry-run 'f))
+       (and (not guix-dry-run) operation-buffer)))))
+
+(cl-defun guix-continue-package-operation-p (profile
+                                             &key install upgrade remove)
+  "Return non-nil if a package operation should be continued.
+Ask a user if needed (see `guix-operation-confirm').
+INSTALL, UPGRADE, REMOVE are 'package action specifications'.
+See `guix-process-package-actions' for details."
+  (or (null guix-operation-confirm)
+      (let* ((entries (guix-ui-get-entries
+                       profile 'package 'id
+                       (append (mapcar #'car install)
+                               (mapcar #'car upgrade)
+                               (mapcar #'car remove))
+                       '(id name version location)))
+             (install-strings (guix-get-package-strings install entries))
+             (upgrade-strings (guix-get-package-strings upgrade entries))
+             (remove-strings  (guix-get-package-strings remove entries)))
+        (if (or install-strings upgrade-strings remove-strings)
+            (let ((buf (get-buffer-create guix-temp-buffer-name)))
+              (with-current-buffer buf
+                (setq-local cursor-type nil)
+                (setq buffer-read-only nil)
+                (erase-buffer)
+                (insert "Profile: " profile "\n\n")
+                (guix-insert-package-strings install-strings "install")
+                (guix-insert-package-strings upgrade-strings "upgrade")
+                (guix-insert-package-strings remove-strings "remove")
+                (let ((win (temp-buffer-window-show
+                            buf
+                            '((display-buffer-reuse-window
+                               display-buffer-at-bottom)
+                              (window-height . fit-window-to-buffer)))))
+                  (prog1 (guix-operation-prompt)
+                    (quit-window nil win)))))
+          (message "Nothing to be done.
+If Guix REPL was restarted, the data is not up-to-date.")
+          nil))))
+
+(defun guix-get-package-strings (specs entries)
+  "Return short package descriptions for performing package actions.
+See `guix-process-package-actions' for the meaning of SPECS.
+ENTRIES is a list of package entries to get info about packages."
+  (delq nil
+        (mapcar
+         (lambda (spec)
+           (let* ((id (car spec))
+                  (outputs (cdr spec))
+                  (entry (guix-entry-by-id id entries)))
+             (when entry
+               (let ((location (guix-entry-value entry 'location)))
+                 (concat (guix-package-entry->name-specification entry)
+                         (when outputs
+                           (concat ":"
+                                   (guix-concat-strings outputs ",")))
+                         (when location
+                           (concat "\t(" location ")")))))))
+         specs)))
+
+(defun guix-insert-package-strings (strings action)
+  "Insert information STRINGS at point for performing package ACTION."
+  (when strings
+    (insert "Package(s) to " (propertize action 'face 'bold) ":\n")
+    (mapc (lambda (str)
+            (insert "  " str "\n"))
+          strings)
+    (insert "\n")))
+
+
+;;; Package 'info'
+
+(guix-ui-info-define-interface package
+  :buffer-name "*Guix Package Info*"
+  :format '(guix-package-info-insert-heading
+            ignore
+            (synopsis ignore (simple guix-package-info-synopsis))
+            ignore
+            (description ignore (simple guix-package-info-description))
+            ignore
+            (outputs simple guix-package-info-insert-outputs)
+            (source simple guix-package-info-insert-source)
+            (location format (format guix-package-location))
+            (home-url format (format guix-url))
+            (license format (format guix-package-info-license))
+            (inputs format (format guix-package-input))
+            (native-inputs format (format guix-package-native-input))
+            (propagated-inputs format
+                               (format guix-package-propagated-input)))
+  :titles '((home-url . "Home page"))
+  :required '(id name version installed non-unique))
+
+(guix-info-define-interface installed-output
+  :format '((path simple (indent guix-file))
+            (dependencies simple (indent guix-file)))
+  :titles '((path . "Store directory"))
+  :reduced? t)
+
+(defface guix-package-info-heading
+  '((t :inherit guix-info-heading))
+  "Face for package name and version headings."
+  :group 'guix-package-info-faces)
+
+(defface guix-package-info-name
+  '((t :inherit font-lock-keyword-face))
+  "Face used for a name of a package."
+  :group 'guix-package-info-faces)
+
+(defface guix-package-info-name-button
+  '((t :inherit button))
+  "Face used for a full name that can be used to describe a package."
+  :group 'guix-package-info-faces)
+
+(defface guix-package-info-version
+  '((t :inherit font-lock-builtin-face))
+  "Face used for a version of a package."
+  :group 'guix-package-info-faces)
+
+(defface guix-package-info-synopsis
+  '((((type tty pc) (class color)) :weight bold)
+    (t :height 1.1 :weight bold :inherit variable-pitch))
+  "Face used for a synopsis of a package."
+  :group 'guix-package-info-faces)
+
+(defface guix-package-info-description
+  '((t))
+  "Face used for a description of a package."
+  :group 'guix-package-info-faces)
+
+(defface guix-package-info-license
+  '((t :inherit font-lock-string-face))
+  "Face used for a license of a package."
+  :group 'guix-package-info-faces)
+
+(defface guix-package-info-location
+  '((t :inherit link))
+  "Face used for a location of a package."
+  :group 'guix-package-info-faces)
+
+(defface guix-package-info-source
+  '((t :inherit link :underline nil))
+  "Face used for a source URL of a package."
+  :group 'guix-package-info-faces)
+
+(defface guix-package-info-installed-outputs
+  '((default :weight bold)
+    (((class color) (min-colors 88) (background light))
+     :foreground "ForestGreen")
+    (((class color) (min-colors 88) (background dark))
+     :foreground "PaleGreen")
+    (((class color) (min-colors 8))
+     :foreground "green")
+    (t :underline t))
+  "Face used for installed outputs of a package."
+  :group 'guix-package-info-faces)
+
+(defface guix-package-info-uninstalled-outputs
+  '((t :weight bold))
+  "Face used for uninstalled outputs of a package."
+  :group 'guix-package-info-faces)
+
+(defface guix-package-info-obsolete
+  '((t :inherit error))
+  "Face used if a package is obsolete."
+  :group 'guix-package-info-faces)
+
+(defcustom guix-package-info-auto-find-source nil
+  "If non-nil, find a source file after pressing a \"Show\" button.
+If nil, just display the source file path without finding."
+  :type 'boolean
+  :group 'guix-package-info)
+
+(defcustom guix-package-info-auto-download-source t
+  "If nil, do not automatically download a source file if it doesn't exist.
+After pressing a \"Show\" button, a derivation of the package
+source is calculated and a store file path is displayed.  If this
+variable is non-nil and the source file does not exist in the
+store, it will be automatically downloaded (with a possible
+prompt depending on `guix-operation-confirm' variable)."
+  :type 'boolean
+  :group 'guix-package-info)
+
+(defvar guix-package-info-download-buffer nil
+  "Buffer from which a current download operation was performed.")
+
+(defvar guix-package-info-output-format "%-10s"
+  "String used to format output names of the packages.
+It should be a '%s'-sequence.  After inserting an output name
+formatted with this string, an action button is inserted.")
+
+(defvar guix-package-info-obsolete-string "(This package is obsolete)"
+  "String used if a package is obsolete.")
+
+(define-button-type 'guix-package-location
+  :supertype 'guix
+  'face 'guix-package-info-location
+  'help-echo "Find location of this package"
+  'action (lambda (btn)
+            (guix-find-location (button-label btn))))
+
+(define-button-type 'guix-package-name
+  :supertype 'guix
+  'face 'guix-package-info-name-button
+  'help-echo "Describe this package"
+  'action (lambda (btn)
+            (guix-buffer-get-display-entries-current
+             'info guix-package-info-type
+             (list (guix-ui-current-profile)
+                   'name (button-label btn))
+             'add)))
+
+(define-button-type 'guix-package-source
+  :supertype 'guix
+  'face 'guix-package-info-source
+  'help-echo ""
+  'action (lambda (_)
+            ;; As a source may not be a real URL (e.g., "mirror://..."),
+            ;; no action is bound to a source button.
+            (message "Yes, this is the source URL. What did you expect?")))
+
+(defun guix-package-info-insert-heading (entry)
+  "Insert package ENTRY heading (name specification) at point."
+  (guix-insert-button
+   (guix-package-entry->name-specification entry)
+   'guix-package-name
+   'face 'guix-package-info-heading))
+
+(defmacro guix-package-info-define-insert-inputs (&optional type)
+  "Define a face and a function for inserting package inputs.
+TYPE is a type of inputs.
+Function name is `guix-package-info-insert-TYPE-inputs'.
+Face name is `guix-package-info-TYPE-inputs'."
+  (let* ((type-str (symbol-name type))
+         (type-name (and type (concat type-str "-")))
+         (type-desc (and type (concat type-str " ")))
+         (face (intern (concat "guix-package-info-" type-name "inputs")))
+         (btn  (intern (concat "guix-package-" type-name "input"))))
+    `(progn
+       (defface ,face
+         '((t :inherit guix-package-info-name-button))
+         ,(concat "Face used for " type-desc "inputs of a package.")
+         :group 'guix-package-info-faces)
+
+       (define-button-type ',btn
+         :supertype 'guix-package-name
+         'face ',face))))
+
+(guix-package-info-define-insert-inputs)
+(guix-package-info-define-insert-inputs native)
+(guix-package-info-define-insert-inputs propagated)
+
+(defun guix-package-info-insert-outputs (outputs entry)
+  "Insert OUTPUTS from package ENTRY at point."
+  (and (guix-entry-value entry 'obsolete)
+       (guix-package-info-insert-obsolete-text))
+  (and (guix-entry-value entry 'non-unique)
+       (guix-entry-value entry 'installed)
+       (guix-package-info-insert-non-unique-text
+        (guix-package-entry->name-specification entry)))
+  (insert "\n")
+  (dolist (output outputs)
+    (guix-package-info-insert-output output entry)))
+
+(defun guix-package-info-insert-obsolete-text ()
+  "Insert a message about obsolete package at point."
+  (guix-info-insert-indent)
+  (guix-format-insert guix-package-info-obsolete-string
+                      'guix-package-info-obsolete))
+
+(defun guix-package-info-insert-non-unique-text (full-name)
+  "Insert a message about non-unique package with FULL-NAME at point."
+  (insert "\n")
+  (guix-info-insert-indent)
+  (insert "Installed outputs are displayed for a non-unique ")
+  (guix-insert-button full-name 'guix-package-name)
+  (insert " package."))
+
+(defun guix-package-info-insert-output (output entry)
+  "Insert OUTPUT at point.
+Make some fancy text with buttons and additional stuff if the
+current OUTPUT is installed (if there is such output in
+`installed' parameter of a package ENTRY)."
+  (let* ((installed (guix-entry-value entry 'installed))
+         (obsolete  (guix-entry-value entry 'obsolete))
+         (installed-entry (cl-find-if
+                           (lambda (entry)
+                             (string= (guix-entry-value entry 'output)
+                                      output))
+                           installed))
+         (action-type (if installed-entry 'delete 'install)))
+    (guix-info-insert-indent)
+    (guix-format-insert output
+                        (if installed-entry
+                            'guix-package-info-installed-outputs
+                          'guix-package-info-uninstalled-outputs)
+                        guix-package-info-output-format)
+    (guix-package-info-insert-action-button action-type entry output)
+    (when obsolete
+      (guix-info-insert-indent)
+      (guix-package-info-insert-action-button 'upgrade entry output))
+    (insert "\n")
+    (when installed-entry
+      (guix-info-insert-entry installed-entry 'installed-output 2))))
+
+(defun guix-package-info-insert-action-button (type entry output)
+  "Insert button to process an action on a package OUTPUT at point.
+TYPE is one of the following symbols: `install', `delete', `upgrade'.
+ENTRY is an alist with package info."
+  (let ((type-str  (capitalize (symbol-name type)))
+        (full-name (guix-package-entry->name-specification entry output)))
+    (guix-info-insert-action-button
+     type-str
+     (lambda (btn)
+       (guix-process-package-actions
+        (guix-ui-current-profile)
+        `((,(button-get btn 'action-type) (,(button-get btn 'id)
+                                           ,(button-get btn 'output))))
+        (current-buffer)))
+     (concat type-str " '" full-name "'")
+     'action-type type
+     'id (or (guix-entry-value entry 'package-id)
+             (guix-entry-id entry))
+     'output output)))
+
+(defun guix-package-info-show-source (entry-id package-id)
+  "Show file name of a package source in the current info buffer.
+Find the file if needed (see `guix-package-info-auto-find-source').
+ENTRY-ID is an ID of the current entry (package or output).
+PACKAGE-ID is an ID of the package which source to show."
+  (let* ((entries (guix-buffer-current-entries))
+         (entry   (guix-entry-by-id entry-id entries))
+         (file    (guix-package-source-path package-id)))
+    (or file
+        (error "Couldn't define file name of the package source"))
+    (let* ((new-entry (cons (cons 'source-file file)
+                            entry))
+           (new-entries (guix-replace-entry entry-id new-entry entries)))
+      (setf (guix-buffer-item-entries guix-buffer-item)
+            new-entries)
+      (guix-buffer-redisplay-goto-button)
+      (if (file-exists-p file)
+          (if guix-package-info-auto-find-source
+              (guix-find-file file)
+            (message "The source store path is displayed."))
+        (if guix-package-info-auto-download-source
+            (guix-package-info-download-source package-id)
+          (message "The source does not exist in the store."))))))
+
+(defun guix-package-info-download-source (package-id)
+  "Download a source of the package PACKAGE-ID."
+  (setq guix-package-info-download-buffer (current-buffer))
+  (guix-package-source-build-derivation
+   package-id
+   "The source does not exist in the store. Download it?"))
+
+(defun guix-package-info-insert-source (source entry)
+  "Insert SOURCE from package ENTRY at point.
+SOURCE is a list of URLs."
+  (if (null source)
+      (guix-format-insert nil)
+    (let* ((source-file (guix-entry-value entry 'source-file))
+           (entry-id    (guix-entry-id entry))
+           (package-id  (or (guix-entry-value entry 'package-id)
+                            entry-id)))
+      (if (null source-file)
+          (guix-info-insert-action-button
+           "Show"
+           (lambda (btn)
+             (guix-package-info-show-source (button-get btn 'entry-id)
+                                            (button-get btn 'package-id)))
+           "Show the source store directory of the current package"
+           'entry-id entry-id
+           'package-id package-id)
+        (unless (file-exists-p source-file)
+          (guix-info-insert-action-button
+           "Download"
+           (lambda (btn)
+             (guix-package-info-download-source
+              (button-get btn 'package-id)))
+           "Download the source into the store"
+           'package-id package-id))
+        (guix-info-insert-value-indent source-file 'guix-file))
+      (guix-info-insert-value-indent source 'guix-package-source))))
+
+(defun guix-package-info-redisplay-after-download ()
+  "Redisplay an 'info' buffer after downloading the package source.
+This function is used to hide a \"Download\" button if needed."
+  (when (buffer-live-p guix-package-info-download-buffer)
+    (with-current-buffer guix-package-info-download-buffer
+      (guix-buffer-redisplay-goto-button))
+    (setq guix-package-info-download-buffer nil)))
+
+(add-hook 'guix-after-source-download-hook
+          'guix-package-info-redisplay-after-download)
+
+
+;;; Package 'list'
+
+(guix-ui-list-define-interface package
+  :buffer-name "*Guix Package List*"
+  :format '((name guix-package-list-get-name 20 t)
+            (version nil 10 nil)
+            (outputs nil 13 t)
+            (installed guix-package-list-get-installed-outputs 13 t)
+            (synopsis guix-list-get-one-line 30 nil))
+  :sort-key '(name)
+  :marks '((install . ?I)
+           (upgrade . ?U)
+           (delete  . ?D)))
+
+(let ((map guix-package-list-mode-map))
+  (define-key map (kbd "e")   'guix-package-list-edit)
+  (define-key map (kbd "x")   'guix-package-list-execute)
+  (define-key map (kbd "i")   'guix-package-list-mark-install)
+  (define-key map (kbd "d")   'guix-package-list-mark-delete)
+  (define-key map (kbd "U")   'guix-package-list-mark-upgrade)
+  (define-key map (kbd "^")   'guix-package-list-mark-upgrades))
+
+(defface guix-package-list-installed
+  '((t :inherit guix-package-info-installed-outputs))
+  "Face used if there are installed outputs for the current package."
+  :group 'guix-package-list-faces)
+
+(defface guix-package-list-obsolete
+  '((t :inherit guix-package-info-obsolete))
+  "Face used if a package is obsolete."
+  :group 'guix-package-list-faces)
+
+(defcustom guix-package-list-generation-marking-enabled nil
+  "If non-nil, allow putting marks in a list with 'generation packages'.
+
+By default this is disabled, because it may be confusing.  For
+example, a package is installed in some generation, so a user can
+mark it for deletion in the list of packages from this
+generation, but the package may not be installed in the latest
+generation, so actually it cannot be deleted.
+
+If you managed to understand the explanation above or if you
+really know what you do or if you just don't care, you can set
+this variable to t.  It should not do much harm anyway (most
+likely)."
+  :type 'boolean
+  :group 'guix-package-list)
+
+(defun guix-package-list-get-name (name entry)
+  "Return NAME of the package ENTRY.
+Colorize it with `guix-package-list-installed' or
+`guix-package-list-obsolete' if needed."
+  (guix-get-string name
+                   (cond ((guix-entry-value entry 'obsolete)
+                          'guix-package-list-obsolete)
+                         ((guix-entry-value entry 'installed)
+                          'guix-package-list-installed))))
+
+(defun guix-package-list-get-installed-outputs (installed &optional _)
+  "Return string with outputs from INSTALLED entries."
+  (guix-get-string
+   (mapcar (lambda (entry)
+             (guix-entry-value entry 'output))
+           installed)))
+
+(defun guix-package-list-marking-check ()
+  "Signal an error if marking is disabled for the current buffer."
+  (when (and (not guix-package-list-generation-marking-enabled)
+             (or (derived-mode-p 'guix-package-list-mode)
+                 (derived-mode-p 'guix-output-list-mode))
+             (eq (guix-ui-current-search-type) 'generation))
+    (error "Action marks are disabled for lists of 'generation packages'")))
+
+(defun guix-package-list-mark-outputs (mark default
+                                       &optional prompt available)
+  "Mark the current package with MARK and move to the next line.
+If PROMPT is non-nil, use it to ask a user for outputs from
+AVAILABLE list, otherwise mark all DEFAULT outputs."
+  (let ((outputs (if prompt
+                     (guix-completing-read-multiple
+                      prompt available nil t)
+                   default)))
+    (apply #'guix-list--mark mark t outputs)))
+
+(defun guix-package-list-mark-install (&optional arg)
+  "Mark the current package for installation and move to the next line.
+With ARG, prompt for the outputs to install (several outputs may
+be separated with \",\")."
+  (interactive "P")
+  (guix-package-list-marking-check)
+  (let* ((entry     (guix-list-current-entry))
+         (all       (guix-entry-value entry 'outputs))
+         (installed (guix-package-installed-outputs entry))
+         (available (cl-set-difference all installed :test #'string=)))
+    (or available
+        (user-error "This package is already installed"))
+    (guix-package-list-mark-outputs
+     'install '("out")
+     (and arg "Output(s) to install: ")
+     available)))
+
+(defun guix-package-list-mark-delete (&optional arg)
+  "Mark the current package for deletion and move to the next line.
+With ARG, prompt for the outputs to delete (several outputs may
+be separated with \",\")."
+  (interactive "P")
+  (guix-package-list-marking-check)
+  (let* ((entry (guix-list-current-entry))
+         (installed (guix-package-installed-outputs entry)))
+    (or installed
+        (user-error "This package is not installed"))
+    (guix-package-list-mark-outputs
+     'delete installed
+     (and arg "Output(s) to delete: ")
+     installed)))
+
+(defun guix-package-list-mark-upgrade (&optional arg)
+  "Mark the current package for upgrading and move to the next line.
+With ARG, prompt for the outputs to upgrade (several outputs may
+be separated with \",\")."
+  (interactive "P")
+  (guix-package-list-marking-check)
+  (let* ((entry (guix-list-current-entry))
+         (installed (guix-package-installed-outputs entry)))
+    (or installed
+        (user-error "This package is not installed"))
+    (when (or (guix-entry-value entry 'obsolete)
+              (y-or-n-p "This package is not obsolete.  Try to upgrade it anyway? "))
+      (guix-package-list-mark-outputs
+       'upgrade installed
+       (and arg "Output(s) to upgrade: ")
+       installed))))
+
+(defun guix-package-mark-upgrades (fun)
+  "Mark all obsolete packages for upgrading.
+Use FUN to perform marking of the current line.  FUN should
+take an entry as argument."
+  (guix-package-list-marking-check)
+  (let ((obsolete (cl-remove-if-not
+                   (lambda (entry)
+                     (guix-entry-value entry 'obsolete))
+                   (guix-buffer-current-entries))))
+    (guix-list-for-each-line
+     (lambda ()
+       (let* ((id (guix-list-current-id))
+              (entry (cl-find-if
+                      (lambda (entry)
+                        (equal id (guix-entry-id entry)))
+                      obsolete)))
+         (when entry
+           (funcall fun entry)))))))
+
+(defun guix-package-list-mark-upgrades ()
+  "Mark all obsolete packages for upgrading."
+  (interactive)
+  (guix-package-mark-upgrades
+   (lambda (entry)
+     (apply #'guix-list--mark
+            'upgrade nil
+            (guix-package-installed-outputs entry)))))
+
+(defun guix-package-execute-actions (fun)
+  "Perform actions on the marked packages.
+Use FUN to define actions suitable for `guix-process-package-actions'.
+FUN should take action-type as argument."
+  (let ((actions (delq nil
+                       (mapcar fun '(install delete upgrade)))))
+    (if actions
+        (guix-process-package-actions (guix-ui-current-profile)
+                                      actions (current-buffer))
+      (user-error "No operations specified"))))
+
+(defun guix-package-list-execute ()
+  "Perform actions on the marked packages."
+  (interactive)
+  (guix-package-execute-actions #'guix-package-list-make-action))
+
+(defun guix-package-list-make-action (action-type)
+  "Return action specification for the packages marked with ACTION-TYPE.
+Return nil, if there are no packages marked with ACTION-TYPE.
+The specification is suitable for `guix-process-package-actions'."
+  (let ((specs (guix-list-get-marked-args action-type)))
+    (and specs (cons action-type specs))))
+
+(defun guix-package-list-edit ()
+  "Go to the location of the current package."
+  (interactive)
+  (guix-edit (guix-list-current-id)))
+
+
+;;; Output 'info'
+
+(guix-ui-info-define-interface output
+  :buffer-name "*Guix Package Info*"
+  :format '((name format (format guix-package-info-name))
+            (version format guix-output-info-insert-version)
+            (output format guix-output-info-insert-output)
+            (synopsis simple (indent guix-package-info-synopsis))
+            (source simple guix-package-info-insert-source)
+            (path simple (indent guix-file))
+            (dependencies simple (indent guix-file))
+            (location format (format guix-package-location))
+            (home-url format (format guix-url))
+            (license format (format guix-package-info-license))
+            (inputs format (format guix-package-input))
+            (native-inputs format (format guix-package-native-input))
+            (propagated-inputs format
+                               (format guix-package-propagated-input))
+            (description simple (indent guix-package-info-description)))
+  :titles guix-package-info-titles
+  :required '(id package-id installed non-unique))
+
+(defun guix-output-info-insert-version (version entry)
+  "Insert output VERSION and obsolete text if needed at point."
+  (guix-info-insert-value-format version
+                                 'guix-package-info-version)
+  (and (guix-entry-value entry 'obsolete)
+       (guix-package-info-insert-obsolete-text)))
+
+(defun guix-output-info-insert-output (output entry)
+  "Insert OUTPUT and action buttons at point."
+  (let* ((installed   (guix-entry-value entry 'installed))
+         (obsolete    (guix-entry-value entry 'obsolete))
+         (action-type (if installed 'delete 'install)))
+    (guix-info-insert-value-format
+     output
+     (if installed
+         'guix-package-info-installed-outputs
+       'guix-package-info-uninstalled-outputs))
+    (guix-info-insert-indent)
+    (guix-package-info-insert-action-button action-type entry output)
+    (when obsolete
+      (guix-info-insert-indent)
+      (guix-package-info-insert-action-button 'upgrade entry output))))
+
+
+;;; Output 'list'
+
+(guix-ui-list-define-interface output
+  :buffer-name "*Guix Package List*"
+  :describe-function 'guix-output-list-describe
+  :format '((name guix-package-list-get-name 20 t)
+            (version nil 10 nil)
+            (output nil 9 t)
+            (installed nil 12 t)
+            (synopsis guix-list-get-one-line 30 nil))
+  :required '(id package-id)
+  :sort-key '(name)
+  :marks '((install . ?I)
+           (upgrade . ?U)
+           (delete  . ?D)))
+
+(let ((map guix-output-list-mode-map))
+  (define-key map (kbd "e")   'guix-output-list-edit)
+  (define-key map (kbd "x")   'guix-output-list-execute)
+  (define-key map (kbd "i")   'guix-output-list-mark-install)
+  (define-key map (kbd "d")   'guix-output-list-mark-delete)
+  (define-key map (kbd "U")   'guix-output-list-mark-upgrade)
+  (define-key map (kbd "^")   'guix-output-list-mark-upgrades))
+
+(defun guix-output-list-mark-install ()
+  "Mark the current output for installation and move to the next line."
+  (interactive)
+  (guix-package-list-marking-check)
+  (let* ((entry     (guix-list-current-entry))
+         (installed (guix-entry-value entry 'installed)))
+    (if installed
+        (user-error "This output is already installed")
+      (guix-list--mark 'install t))))
+
+(defun guix-output-list-mark-delete ()
+  "Mark the current output for deletion and move to the next line."
+  (interactive)
+  (guix-package-list-marking-check)
+  (let* ((entry     (guix-list-current-entry))
+         (installed (guix-entry-value entry 'installed)))
+    (if installed
+        (guix-list--mark 'delete t)
+      (user-error "This output is not installed"))))
+
+(defun guix-output-list-mark-upgrade ()
+  "Mark the current output for upgrading and move to the next line."
+  (interactive)
+  (guix-package-list-marking-check)
+  (let* ((entry     (guix-list-current-entry))
+         (installed (guix-entry-value entry 'installed)))
+    (or installed
+        (user-error "This output is not installed"))
+    (when (or (guix-entry-value entry 'obsolete)
+              (y-or-n-p "This output is not obsolete.  Try to upgrade it anyway? "))
+      (guix-list--mark 'upgrade t))))
+
+(defun guix-output-list-mark-upgrades ()
+  "Mark all obsolete package outputs for upgrading."
+  (interactive)
+  (guix-package-mark-upgrades
+   (lambda (_) (guix-list--mark 'upgrade))))
+
+(defun guix-output-list-execute ()
+  "Perform actions on the marked outputs."
+  (interactive)
+  (guix-package-execute-actions #'guix-output-list-make-action))
+
+(defun guix-output-list-make-action (action-type)
+  "Return action specification for the outputs marked with ACTION-TYPE.
+Return nil, if there are no outputs marked with ACTION-TYPE.
+The specification is suitable for `guix-process-output-actions'."
+  (let ((ids (guix-list-get-marked-id-list action-type)))
+    (and ids (cons action-type
+                   (mapcar #'guix-package-id-and-output-by-output-id
+                           ids)))))
+
+(defun guix-output-list-describe (ids)
+  "Describe outputs with IDS (list of output identifiers).
+See `guix-package-info-type'."
+  (if (eq guix-package-info-type 'output)
+      (guix-buffer-get-display-entries
+       'info 'output
+       (cl-list* (guix-ui-current-profile) 'id ids)
+       'add)
+    (let ((pids (mapcar (lambda (oid)
+                          (car (guix-package-id-and-output-by-output-id
+                                oid)))
+                        ids)))
+      (guix-buffer-get-display-entries
+       'info 'package
+       (cl-list* (guix-ui-current-profile)
+                 'id (cl-remove-duplicates pids))
+       'add))))
+
+(defun guix-output-list-edit ()
+  "Go to the location of the current package."
+  (interactive)
+  (guix-edit (guix-entry-value (guix-list-current-entry)
+                               'package-id)))
+
+
+;;; Interactive commands
+
+(defvar guix-package-search-params '(name synopsis description)
+  "Default list of package parameters for searching by regexp.")
+
+(defvar guix-package-search-history nil
+  "A history of minibuffer prompts.")
+
+;;;###autoload
+(defun guix-search-by-name (name &optional profile)
+  "Search for Guix packages by NAME.
+NAME is a string with name specification.  It may optionally contain
+a version number.  Examples: \"guile\", \"guile-2.0.11\".
+
+If PROFILE is nil, use `guix-current-profile'.
+Interactively with prefix, prompt for PROFILE."
+  (interactive
+   (list (read-string "Package name: " nil 'guix-package-search-history)
+         (and current-prefix-arg
+              (guix-profile-prompt))))
+  (guix-package-get-display profile 'name name))
+
+;;;###autoload
+(defun guix-search-by-regexp (regexp &optional params profile)
+  "Search for Guix packages by REGEXP.
+PARAMS are package parameters that should be searched.
+If PARAMS are not specified, use `guix-package-search-params'.
+
+If PROFILE is nil, use `guix-current-profile'.
+Interactively with prefix, prompt for PROFILE."
+  (interactive
+   (list (read-regexp "Regexp: " nil 'guix-package-search-history)
+         nil
+         (and current-prefix-arg
+              (guix-profile-prompt))))
+  (guix-package-get-display profile 'regexp regexp
+                            (or params guix-package-search-params)))
+
+;;;###autoload
+(defun guix-installed-packages (&optional profile)
+  "Display information about installed Guix packages.
+If PROFILE is nil, use `guix-current-profile'.
+Interactively with prefix, prompt for PROFILE."
+  (interactive
+   (list (and current-prefix-arg
+              (guix-profile-prompt))))
+  (guix-package-get-display profile 'installed))
+
+;;;###autoload
+(defun guix-obsolete-packages (&optional profile)
+  "Display information about obsolete Guix packages.
+If PROFILE is nil, use `guix-current-profile'.
+Interactively with prefix, prompt for PROFILE."
+  (interactive
+   (list (and current-prefix-arg
+              (guix-profile-prompt))))
+  (guix-package-get-display profile 'obsolete))
+
+;;;###autoload
+(defun guix-all-available-packages (&optional profile)
+  "Display information about all available Guix packages.
+If PROFILE is nil, use `guix-current-profile'.
+Interactively with prefix, prompt for PROFILE."
+  (interactive
+   (list (and current-prefix-arg
+              (guix-profile-prompt))))
+  (guix-package-get-display profile 'all-available))
+
+;;;###autoload
+(defun guix-newest-available-packages (&optional profile)
+  "Display information about the newest available Guix packages.
+If PROFILE is nil, use `guix-current-profile'.
+Interactively with prefix, prompt for PROFILE."
+  (interactive
+   (list (and current-prefix-arg
+              (guix-profile-prompt))))
+  (guix-package-get-display profile 'newest-available))
+
+(provide 'guix-ui-package)
+
+;;; guix-ui-package.el ends here
diff --git a/emacs/guix.el b/emacs/guix.el
deleted file mode 100644
index 12dd4a2553..0000000000
--- a/emacs/guix.el
+++ /dev/null
@@ -1,210 +0,0 @@
-;;; guix.el --- Interface for GNU Guix package manager
-
-;; Copyright © 2014, 2015 Alex Kost <alezost@gmail.com>
-
-;; Package-Requires: ((geiser "0.3"))
-;; Keywords: tools
-
-;; This file is part of GNU Guix.
-
-;; GNU Guix is free software; you can redistribute it and/or modify
-;; it under the terms of the GNU General Public License as published by
-;; the Free Software Foundation, either version 3 of the License, or
-;; (at your option) any later version.
-
-;; GNU Guix is distributed in the hope that it will be useful,
-;; but WITHOUT ANY WARRANTY; without even the implied warranty of
-;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-;; GNU General Public License for more details.
-
-;; You should have received a copy of the GNU General Public License
-;; along with this program.  If not, see <http://www.gnu.org/licenses/>.
-
-;;; Commentary:
-
-;; This package provides an interface for searching, listing and getting
-;; information about Guix packages and generations; and for
-;; installing/upgrading/removing packages.
-
-;;; Code:
-
-(require 'guix-base)
-(require 'guix-list)
-(require 'guix-info)
-(require 'guix-utils)
-(require 'guix-read)
-
-(defgroup guix nil
-  "Interface for Guix package manager."
-  :prefix "guix-"
-  :group 'external)
-
-(defgroup guix-faces nil
-  "Guix faces."
-  :group 'guix
-  :group 'faces)
-
-(defcustom guix-list-single-package nil
-  "If non-nil, list a package even if it is the only matching result.
-If nil, show a single package in the info buffer."
-  :type 'boolean
-  :group 'guix)
-
-(defvar guix-search-params '(name synopsis description)
-  "Default list of package parameters for searching by regexp.")
-
-(defvar guix-search-history nil
-  "A history of minibuffer prompts.")
-
-(defun guix-get-show-packages (profile search-type &rest search-values)
-  "Search for packages and show results.
-
-If PROFILE is nil, use `guix-current-profile'.
-
-See `guix-ui-get-entries' for the meaning of SEARCH-TYPE and
-SEARCH-VALUES.
-
-Results are displayed in the list buffer, unless a single package
-is found and `guix-list-single-package' is nil."
-  (let* ((args    (cl-list* (or profile guix-current-profile)
-                            search-type search-values))
-         (entries (guix-buffer-get-entries
-                   'list guix-package-list-type args)))
-    (if (or guix-list-single-package
-            (null entries)
-            (cdr entries))
-        (guix-buffer-display-entries
-         entries 'list guix-package-list-type args 'add)
-      (guix-buffer-get-display-entries
-       'info guix-package-info-type args 'add))))
-
-(defun guix-get-show-generations (profile search-type &rest search-values)
-  "Search for generations and show results.
-
-If PROFILE is nil, use `guix-current-profile'.
-
-See `guix-ui-get-entries' for the meaning of SEARCH-TYPE and
-SEARCH-VALUES."
-  (let ((args (cl-list* (or profile guix-current-profile)
-                        search-type search-values)))
-    (guix-buffer-get-display-entries
-     'list 'generation args 'add)))
-
-;;;###autoload
-(defun guix-search-by-name (name &optional profile)
-  "Search for Guix packages by NAME.
-NAME is a string with name specification.  It may optionally contain
-a version number.  Examples: \"guile\", \"guile-2.0.11\".
-
-If PROFILE is nil, use `guix-current-profile'.
-Interactively with prefix, prompt for PROFILE."
-  (interactive
-   (list (read-string "Package name: " nil 'guix-search-history)
-         (and current-prefix-arg
-              (guix-profile-prompt))))
-  (guix-get-show-packages profile 'name name))
-
-;;;###autoload
-(defun guix-search-by-regexp (regexp &optional params profile)
-  "Search for Guix packages by REGEXP.
-PARAMS are package parameters that should be searched.
-If PARAMS are not specified, use `guix-search-params'.
-
-If PROFILE is nil, use `guix-current-profile'.
-Interactively with prefix, prompt for PROFILE."
-  (interactive
-   (list (read-regexp "Regexp: " nil 'guix-search-history)
-         nil
-         (and current-prefix-arg
-              (guix-profile-prompt))))
-  (guix-get-show-packages profile 'regexp regexp
-                          (or params guix-search-params)))
-
-;;;###autoload
-(defun guix-installed-packages (&optional profile)
-  "Display information about installed Guix packages.
-If PROFILE is nil, use `guix-current-profile'.
-Interactively with prefix, prompt for PROFILE."
-  (interactive
-   (list (and current-prefix-arg
-              (guix-profile-prompt))))
-  (guix-get-show-packages profile 'installed))
-
-;;;###autoload
-(defun guix-obsolete-packages (&optional profile)
-  "Display information about obsolete Guix packages.
-If PROFILE is nil, use `guix-current-profile'.
-Interactively with prefix, prompt for PROFILE."
-  (interactive
-   (list (and current-prefix-arg
-              (guix-profile-prompt))))
-  (guix-get-show-packages profile 'obsolete))
-
-;;;###autoload
-(defun guix-all-available-packages (&optional profile)
-  "Display information about all available Guix packages.
-If PROFILE is nil, use `guix-current-profile'.
-Interactively with prefix, prompt for PROFILE."
-  (interactive
-   (list (and current-prefix-arg
-              (guix-profile-prompt))))
-  (guix-get-show-packages profile 'all-available))
-
-;;;###autoload
-(defun guix-newest-available-packages (&optional profile)
-  "Display information about the newest available Guix packages.
-If PROFILE is nil, use `guix-current-profile'.
-Interactively with prefix, prompt for PROFILE."
-  (interactive
-   (list (and current-prefix-arg
-              (guix-profile-prompt))))
-  (guix-get-show-packages profile 'newest-available))
-
-;;;###autoload
-(defun guix-generations (&optional profile)
-  "Display information about all generations.
-If PROFILE is nil, use `guix-current-profile'.
-Interactively with prefix, prompt for PROFILE."
-  (interactive
-   (list (and current-prefix-arg
-              (guix-profile-prompt))))
-  (guix-get-show-generations profile 'all))
-
-;;;###autoload
-(defun guix-last-generations (number &optional profile)
-  "Display information about last NUMBER generations.
-If PROFILE is nil, use `guix-current-profile'.
-Interactively with prefix, prompt for PROFILE."
-  (interactive
-   (list (read-number "The number of last generations: ")
-         (and current-prefix-arg
-              (guix-profile-prompt))))
-  (guix-get-show-generations profile 'last number))
-
-;;;###autoload
-(defun guix-generations-by-time (from to &optional profile)
-  "Display information about generations created between FROM and TO.
-FROM and TO should be time values.
-If PROFILE is nil, use `guix-current-profile'.
-Interactively with prefix, prompt for PROFILE."
-  (interactive
-   (list (guix-read-date "Find generations (from): ")
-         (guix-read-date "Find generations (to): ")
-         (and current-prefix-arg
-              (guix-profile-prompt))))
-  (guix-get-show-generations profile 'time
-                             (float-time from)
-                             (float-time to)))
-
-;;;###autoload
-(defun guix-edit (id-or-name)
-  "Edit (go to location of) package with ID-OR-NAME."
-  (interactive (list (guix-read-package-name)))
-  (let ((loc (guix-package-location id-or-name)))
-    (if loc
-        (guix-find-location loc)
-      (message "Couldn't find package location."))))
-
-(provide 'guix)
-
-;;; guix.el ends here