How Do I...
###Change settings (fonts, line numbers…)?
Settings are represented as behaviors in Light Table. To modify your user behaviors, execute the Settings: User behaviors command and modify the file that is opened. For example, to turn on the line number gutter, find the :editor tag and in the square brackets type “number”. Then select Editor: Show line numbers behavior. This workflow lets you search for the behavior you want via the auto-complete and then the helper will show you what parameters are needed (if any) for that behavior.
All settings in Light Table work this way and behaviors give you the ability to fundamentally change the functionality of Light Table.
###Configure behaviors
To add a behavior to your user.behaviors file, add a vector in the format [:TAG :COMMAND :ARG1 :ARG2 ...] e.g. [:editor :lt.objs.editor/no-wrap]. If a command takes arguments append them after the command e.g. [:app :lt.objs.app/set-default-zoom-level 0.8]. Behaviors that are set by default can be subtracted/removed by prefixing the command with ‘-‘ e.g. [:editor :-lt.objs.editor/no-wrap].
###Change theme
To set the editor theme execute the Settings: User behaviors command, type [:editor :lt.objs.style/set-theme "" ] and in between quotation marks type a theme name (auto-complete will help you here). To see what different themes look like, try the CodeMirror theme demo. Note that some themes listed there may not be available because LightTable may not be on the same CodeMirror version as the demo. To try third party themes, like these ones, download them and add an entry for it in user.behaviors file: [:app :lt.objs.style/provide-theme "theme-name" "/full/path/to/theme/css"]. Once a theme is provided you can set it with the aforementioned set-theme.
###Evaluate code inline?
Within an editor, eval a single “block” (or form if you’re used to LISP) is bound to Cmd/Ctrl+Enter by default and evaling an entire file is bound to Cmd/Ctrl+Shift+Enter. Not all file types know how to eval, to find out what kinds of clients are available for evaluation, open the connect tab and press the “Add Connection” button. This will give you a list of all the clients Light Table knows how to start.
###Change keybindings?
Keybindings are defined in .keymap files in Light Table. To open the user keymap, execute the Settings: User keymap command. To see the default keybindings you can execute the Settings: Default keymap command. Keys are bound based on context (tag), which allows you to create contextual command schemes.
###Configure keybindings
To add a keybinding to your user.keymap file, add a vector in the format [:TAG "KEYBINDING" :COMMAND] e.g. [:editor "alt-w" :editor.watch.watch-selection]. If a command takes arguments wrap the command and its arguments in a parentheses e.g. [:editor "alt-(" (:paredit.select.parent "(")]. If you want to bind multiple commands to the same keybinding, use a simple vector for the whole binding-command e.g. [:editor "alt-(" (:paredit.select.parent "(") :smart-indent-selection]. Keybindings that are set by default can be subtracted/removed by prefixing the key with ‘-‘ e.g. [:app "-ctrl-shift-d" :docs.search.show].
###Split windows?
You can create a new tabset by either right clicking in the tab area and selecting New tabset or by using the Tabs: Add a tabset command in the command bar. To close a tabset you can either use the Tabs: Remove active tabset command or resize it such that it has 0 width.
###Open a new window?
By default, Cmd/Ctrl+Shift+N is bound to the command Window: Open new window, which you can also just execute from the command tab.
###Open a browser tab for live modification?
You can open a browser tab by either using the Browser: add browser tab command or by choosing the browser client type form the “Add Connection” menu in the connect tab. Once open, it is now available as an evaluation client and Cmd/Ctrl+R is bound to refreshing it.
###Bring up auto-completion?
Auto-complete is bound to the Tab key if there’s some non-space character preceding the cursor, otherwise a tab is inserted.
###Eval an arbitraty unit of code?
If you have something selected Light Table will send the selection text for eval if you press Cmd/Ctrl+Enter.
###Eval Clojure?
To eval Clojure, open a .clj file and press Cmd/Ctrl+Enter. Light Table will find a leiningen project if there is one or it will use it’s local REPL client to evaluate your code.
###Eval ClojureScript
You can eval ClojureScript a couple of different ways. For your ClojureScript project, building your cljs assets and then pressing Cmd/Ctrl+Enter is recommended. To read more about this workflow, see the Clojure plugin REAMDE.
###Eval Javascript in NodeJS?
To eval in a Node process:
- Go to the
connecttab - Click “Add Connection”
- Select “NodeJS”
- Choose a Javascript file to start the node server with.
- Open a .js file
- Press Cmd/Ctrl+Enter
- Select your nodejs client from the popup
###Eval Python?
The easiest way is to simply open a Python file and press Cmd/Ctrl+Enter. This will cause Light Table to start a python client that it can then send code to.
###Use IPython for Python eval?
By default, if Light Table can find a recent IPython installed on your machine, it will use it to provide a much more robust python evaluation environment. If you don’t have it installed, follow these instructions to do so (make sure you install pyzmq as well). With it you can use matplotlib and pylab inline. To see if Light Table is using IPython for Python eval, open the connect tab and look to see if your Python client has the type of ipython. Note that in order for Light Table to use IPython, pyzmq also needs to be installed.
###See the output from STDOUT and STDERR?
When you print from a client, it will appear in the Console, which can be opened by clicking the blue number in the bottom right corner of the editor, from the View menu, or by using the Console: Toggle console command.
###Use a different client once I’ve evaled something?
From the connect tab, find the client and make sure the editor you evaled in is active. The connected client(s) will appear highlighted. Click the “unset” button to force Light Table to re-evaluate what clients are available to eval in the editor.
###Close a client?
From the connect tab, find the client and click the “disconnect” button.
###Install a Plugin
Open the command pane and find the command “Plugins: Show Plugin Manager”. In the manager, search for a plugin. Hover over a search result and click its install button.
###Toggle Vim keybindings?
Install the Vim plugin using the Plugin Manager and then run the command App: Reload
behaviors. If Emacs is already installed, disable it in users.behaviors with [:editor
:-lt.plugins.emacs/activate-emacs].
###Toggle Emacs keybindings?
Install the Emacs plugin using the Plugin Manager and then run the command App: Reload
behaviors. If Vim is already installed, disable it in users.behaviors with [:editor
:-lt.plugins.vim/activate-vim].
###Exclude files from the workspace?
Open your user behaviors and in the :app tag start typing “ignore”. Select the Files: Set ignore pattern behavior.
###Change the location of the lighttable directory?
You can use the environment variable LTHOME to tell the command line scripts where to find LT.
###Find out what version of Light Table I’m using?
Use the App: Light Table version command from the command tab.
###Plugins directory
The plugins directory varies depending on the platform:
- Mac:
~/Library/Application\ Support/LightTable/plugins - Linux:
~/.config/LightTable/plugins - Windows:
%APPDATALOCAL%/LightTable/plugins
Alternatively, you can see your location from running the command App: Light Table version.
###User plugin
Your complete configuration, including plugins you’ve installed, is stored in a User plugin. Since the User plugin is just a directory, you can share it by putting it under revision control e.g. git and uploading it to a service like Github. To explore it, add it to your workspace with the command Settings: Add User plugin to workspace. Any custom keybindings and behaviors are added to user.keymap and user.behaviors. To write commands, behaviors and more, see src/lt/plugins/user.cljs. To open your user.cljs at anytime use the command Settings: User script. Inside the default user.cljs is an example command and behavior. If you’re upgrading Light Table, you will need to add two behaviors to user.behaviors in order for the examples to work:
[:app :lt.objs.plugins/load-js "user_compiled.js"]
[:user.hello :lt.plugins.user/on-close-destroy]
Run the command User: Say Hello to see your own command!
###Write a plugin
Plugins are a great way to share your Light Table enhancement with the community. The recommended way to generate one is with lein new lt-plugin my-plugin --to-dir MyPlugin. Make sure to run that it in your plugin directory. Add the generated plugin to your workspace and open the generated .cljs file. With your LT UI connection set up, eval the file with Cmd-Shift Enter. Now try your new plugin command Say Hello! For more about writing plugins, see this wiki page.
###Submit a plugin
If it’s your first time submitting a plugin, make sure you have a valid plugin.edn. Fill out the keys as follows:
:name*: Camel case is recommended:version*: Must be in format X.X.X e.g. 0.1.4:source*: Must be a github url e.g. https://github.com/USER/PLUGIN:behaviors*: Refers to the behaviors file which is needed to load the plugin and define any keybinding or behavior.:desc: Primary means users can find your plugin:author: Your name and another useful way to find your plugin
* Means the field is required.
When releasing a new version, you must update the :version key and push the new git tag e.g. git tag X.X.X && git push --tags. With your updated plugin.edn, add or update your plugin to the plugin metadata repository using these instructions.