REBL with Lein REPL example

A simple example of how to setup REBL to run within lein repl.

Installation

1. First download REBL

2. Extract the REBL jar file and move it into resources/REBL-xxxx.jar.

3. Update your project.clj file to use Clojure 1.10.0-RC2 or higher, core async, and add the REBL jar to your resource paths:

   (defproject rebl-test "0.1.0-SNAPSHOT"
     :description "FIXME: write description"
     :url "http://example.com/FIXME"
     :dependencies [[org.clojure/clojure "1.10.0-RC2"]
                    [org.clojure/core.async "0.4.490"]]
     :resource-paths ["resources/REBL-0.9.108.jar"]
     :main ^:skip-aot rebl-test.core
     :target-path "target/%s"
     :profiles {:uberjar {:aot :all}})

4. In your terminal run lein repl to start an nrepl server and client.

5. Once the Leiningen repl loads, run the following:

   (require '[cognitect.rebl :as rebl])
   (rebl/ui)

   Example:

   nREPL server started on port 57844 on host 127.0.0.1 - nrepl://127.0.0.1:57844
   REPL-y 0.3.7, nREPL 0.2.12
   Clojure 1.10.0-RC2
   Java HotSpot(TM) 64-Bit Server VM 1.8.0_144-b01
       Docs: (doc function-name-here)
             (find-doc "part-of-name-here")
     Source: (source function-name-here)
    Javadoc: (javadoc java-object-or-class-here)
       Exit: Control+D or (exit) or (quit)
    Results: Stored in vars *1, *2, *3, an exception in *e
   
   rebl-test.core=> (require '[cognitect.rebl :as rebl])
   nil
   rebl-test.core=> (rebl/ui)
   nil

The REBL UI should display and you are good to go 😄 🍺

---

Alternate Installation & Configuration Approaches

Dev Profile

You may want to only include access to the REBL jar while in development. Below is one of many ways to achieve this:

(defproject rebl-test "0.1.0-SNAPSHOT"
  :description "FIXME: write description"
  :url "http://example.com/FIXME"
  :dependencies [[org.clojure/clojure "1.9.0"]]
  :main ^:skip-aot rebl-test.core
  :target-path "target/%s"
  :profiles {:uberjar {:aot :all}
             :dev [:project/dev :profiles/dev]
             :project/dev {:dependencies [[org.clojure/clojure "1.10.0-RC2"]
                                          [org.clojure/core.async "0.4.490"]]
                           :resource-paths ["env/dev/resources"]}})

TIP: If you replace :dev profile with :repl the configuration only applies when running lein repl. Read the lein profiles docs for more configuration options.

Lein Local Repo

1. Add lein-localrepo plugin to profiles.clj
2. Download REBL and extract the zip.
3. Install the JAR as a shared maven repo by running this command relative to the jar:

   lein localrepo install REBL-0.9.108.jar com.cognitect/rebl 0.9.108

4. Now you can add it to your dependencies:

   [com.cognitect/rebl "0.9.108"]