add notes about setting up osx dictionary

Also fill paragraphs in osx layer readme file.

layers/+os/osx/README.org

@@ -14,23 +14,21 @@
  - [[#future-work][Future Work]]
 
 * Description
-Spacemacs is not just emacs+vim. It can have OSX keybindings too!
-This layer globally defines common OSX keybindings. ~⌘~ is set to
-~super~ and ~⌥~ is set to ~meta~. Aside from that, there's nothing
-much, really.
+Spacemacs is not just emacs+vim. It can have OSX keybindings too! This layer
+globally defines common OSX keybindings. ~⌘~ is set to ~super~ and ~⌥~ is set to
+~meta~. Aside from that, there's nothing much, really.
 
 While in =dired= this layer will try to use =gls= instead of =ls=.
 
 * Philosophy
-While this layer enables common OSX bindings, it does not implement
-OSX navigation keybindings. Spacemacs is meant to be used with evil,
-and we encourage you to do so :)
+While this layer enables common OSX bindings, it does not implement OSX
+navigation keybindings. Spacemacs is meant to be used with evil, and we
+encourage you to do so :)
 
 * Install
 ** Layer
 To use this configuration layer, add it to your =~/.spacemacs=. You will need to
-add =osx= to the existing =dotspacemacs-configuration-layers= list in this
-file.
+add =osx= to the existing =dotspacemacs-configuration-layers= list in this file.
 
 *** Use with non-US keyboard layouts
 If you need the ~⌥~ key to type common characters such as ={[]}~= which is usual
@@ -53,7 +51,18 @@ key.
 
 *** Define words using OS X Dictionary
 
-This layer by default enables defining words under point ~SPC x w d~ using OS X Dictionary.
+This layer by default enables defining words under point ~SPC x w d~ using OS X
+Dictionary. In some cases you might want to manually setup dictionary to use.
+For example,
+
+#+BEGIN_SRC emacs-lisp
+  (setq-default dotspacemacs-configuration-layers '(
+     (osx :variables osx-dictionary-dictionary-choice "English")))
+#+END_SRC
+
+To get the list of available dictionaries call =osx/list-available-dictionaries=
+function.
+
 You can disable it by setting =osx-use-dictionary-app= variable to =nil=:
 
 #+BEGIN_SRC emacs-lisp
@@ -70,21 +79,22 @@ To get =gls= install coreutils homebrew:
 
 * Key Bindings
 
-| Key Binding | Description       |
-|-------------+-------------------|
-| ~⌘ =~       | Scale up text     |
-| ~⌘ -~       | Scale down text   |
-| ~⌘ q~       | Quit              |
-| ~⌘ v~       | Paste             |
-| ~⌘ c~       | Copy              |
-| ~⌘ x~       | Cut               |
-| ~⌘ a~       | Select all        |
-| ~⌘ w~       | Close window      |
-| ~⌘ W~       | Close frame       |
-| ~⌘ n~       | New frame         |
-| ~⌘ z~       | Undo              |
-| ~⌘ Z~       | Redo              |
-| ~⌃ ⌘ f~     | Toggle fullscreen |
+| Key Binding | Description                 |
+|-------------+-----------------------------|
+| ~⌘ =~       | Scale up text               |
+| ~⌘ -~       | Scale down text             |
+| ~⌘ q~       | Quit                        |
+| ~⌘ v~       | Paste                       |
+| ~⌘ c~       | Copy                        |
+| ~⌘ x~       | Cut                         |
+| ~⌘ a~       | Select all                  |
+| ~⌘ w~       | Close window                |
+| ~⌘ W~       | Close frame                 |
+| ~⌘ n~       | New frame                   |
+| ~⌘ z~       | Undo                        |
+| ~⌘ Z~       | Redo                        |
+| ~⌃ ⌘ f~     | Toggle fullscreen           |
+| ~SPC x w d~ | Define word under the point |
 
 * Future Work
 - Allow user to choose from either ~hyper~ or ~super~ as ~⌘~. This is an option

layers/+os/osx/funcs.el

@@ -0,0 +1,18 @@
+;;; config.el --- OSX Layer packages File for Spacemacs
+;;
+;; Copyright (c) 2012-2016 Sylvain Benner & Contributors
+;;
+;; Author: Boris Buliga <boris@d12frosted.io>
+;; URL: https://github.com/syl20bnr/spacemacs
+;;
+;; This file is not part of GNU Emacs.
+;;
+;;; License: GPLv3
+
+(defun osx/list-available-dictionaries ()
+  "Get list of available dictionaries.
+
+Useful when setting `osx-dictionary-dictionary-choice'."
+  (interactive)
+  (message (shell-command-to-string
+     (format "%s -l" (osx-dictionary-cli-find-or-recompile)))))

layers/+os/osx/packages.el

@@ -84,6 +84,9 @@
   (use-package osx-dictionary
     :if osx-use-dictionary-app
     :init (spacemacs/set-leader-keys "xwd" 'osx-dictionary-search-pointer)
+    :commands (osx-dictionary-search-pointer
+               osx-dictionary-search-input
+               osx-dictionary-cli-find-or-recompile)
     :config
     (progn
       (evilified-state-evilify-map osx-dictionary-mode-map