LightTable

This workshop will use LightTable to help you discover Clojure.

I have found LightTable to be one of the best tools to help you learn Clojure, especially the highly interactive Instarepl that evaluates your Clojure code as you type.

LightTable is a modern development tool that supports Clojure, ClojureScript, JavaScript and Python languages. The tool is open source and written in Clojure & ClojureScript (with a little JavaScript & CSS)

Install Lighttable from lighttable.com

Linux Extract the contents of the downloaded lighttable file to a suitable directory (/usr/local or /opt or ~/apps). Make sure the LightTable file in the extracted folder is accessible via the system $PATH.

MacOSX Install the lighttable.dmg file just as any other MacOSX package

Windows Download the windows zip file for LightTable and extract the installer, following the instructions inside the installer.

Useful LightTable configurations

Open the user behaviours file, Ctrl-space user behaviors and add any of the following configurations

This opens the User Behaviours file for editing. When you save the file, Ctrl-s, changes are applied immediately. Add any of the following options you wish:

Open Workspace on startup Show the workspace browser when you run LightTable, so you can see all the projects you have added and open files easily.

[:app :lt.objs.sidebar.workspace/workspace.open-on-start]

automatic closing of parentesses Enabling auto-closing parens. - not recommended for non-English keyboard layouts

[:app :lt.objs.settings/pair-keymap-diffs]

show line numbers

[:editor :lt.objs.editor/line-numbers]

don't wrap lines Dont wrap a line of text around if they are to long for the screen:

[:editor :lt.objs.editor/no-wrap]

Sample User Behaviours file

[
 ;; The app tag is kind of like global scope. You assign behaviors that affect
 ;; all of Light Table to it.
 [:app :lt.objs.style/set-skin "dark"]
 [:app :lt.objs.plugins/load-js "user_compiled.js"]

 ;; The editor tag is applied to all editors
 [:editor :lt.objs.editor/no-wrap]
 [:editor :lt.objs.style/set-theme "default"]
 [:editor :lt.objs.style/font-settings "Sans" 16 1.2]
 [:app :lt.objs.settings/pair-keymap-diffs]
 [:editor :lt.objs.editor/line-numbers]

 ;; Here we can add behaviors to just clojure editors
 [:editor.clojure :lt.plugins.clojure/print-length 1000]

 ;; Behaviors specific to a user-defined object
 [:user.hello :lt.plugins.user/on-close-destroy]

 ;; To subtract a behavior, prefix the name with '-' e.g.
 ;; [:app :-lt.objs.intro/show-intro]
]

Using LightTable

LightTable has an online tutorial entitled Getting started with LightTable

I mainly use the Instarepl in LightTable. I create a project first with Leiningen, open the project directory in the LightTable workspace and oopen any files I want to work with. I then connect the open editor window for the file to an Instarepl.

my approach is documented in the quick demo section of my Clojure & LightTable slides from JAXLondon 2013. This should be pulled into this workshop into its own section