Add documentation to embed an nREPL, specifically for Rebel Readline

doc/vim-iced.txt

@@ -14,6 +14,7 @@ CONTENTS                                                    *vim-iced-contents*
       Leiningen                |vim-iced-manual-leiningen|
       Boot                     |vim-iced-manual-boot|
       shadow-cljs              |vim-iced-manual-shadow-cljs|
+      Rebel Readline           |vim-iced-manual-rebel-readline|
     Boost by Python            |vim-iced-install-python|
     Docker                     |vim-iced-install-docker|
   REPL Connection              |vim-iced-repl-connection|
@@ -217,6 +218,55 @@ SHADOW-CLJS~
 <
   To start CLJS REPL, see |vim-iced-shadow-cljs|.
 
+                                              *vim-iced-manual-rebel-readline*
+REBEL READLINE~
+
+  If you use Rebel Readline or want to embed an nREPL in your application,
+  then one approach is to create a `user.clj` with the following:
+>
+  (ns user
+    (:require [nrepl.server :as nrepl-server]
+              [clojure.java.io :as io]))
+
+  (def nrepl-port 7888)
+  (defonce nrepl-server (atom nil))
+
+  (defn cider-middleware
+    "Get cider middleware, see 
+    https://github.com/clojure-emacs/cider-nrepl/issues/447"
+    []
+    (require 'cider.nrepl)
+    (map ns-resolve 
+       ['cider.nrepl 'cider.nrepl 'cider.nrepl 'cider.nrepl 'cider.nrepl 'cider.nrepl 'cider.nrepl 'cider.nrepl 'cider.nrepl 'cider.nrepl 'cider.nrepl 'cider.nrepl 'cider.nrepl 'cider.nrepl] 
+       ['wrap-classpath 'wrap-clojuredocs 'wrap-complete 'wrap-debug 'wrap-format 'wrap-info 'wrap-macroexpand 'wrap-ns 'wrap-out 'wrap-spec 'wrap-test 'wrap-trace 'wrap-undef 'wrap-xref]))
+
+  (defn dev-middleware []
+    (mapcat (fn [[ns syms]] (require ns) (map (partial ns-resolve ns) syms))
+    [['refactor-nrepl.middleware ['wrap-refactor]] ['iced.nrepl ['wrap-iced]]]))
+
+  (defn nrepl-handler
+    "Re-implement cider-nrepl-handler so we can add middleware to the default list"
+    []
+    (apply nrepl-server/default-handler (concat (cider-middleware) (dev-middleware))))
+
+  (defn start-nrepl-server! []
+    (reset!
+      nrepl-server
+        (nrepl-server/start-server :port nrepl-port :handler (nrepl-handler)))
+    (println "Cider nREPL server started on port" nrepl-port)
+    (spit ".nrepl-port" nrepl-port))
+
+  (defn stop-nrepl-server! []
+    (when (not (nil? @nrepl-server))
+      (nrepl-server/stop-server @nrepl-server)
+      (println "Cider nREPL server on port" nrepl-port "stopped")
+      (reset! nrepl-server nil)
+      (io/delete-file ".nrepl-port" true)
+      (System/exit 0)))
+<
+  Start the Rebel Readline REPL and from it's prompt start the nREPL server 
+  using `start-nrepl-server!`, then in Vim do `:IcedConnect`.
+
 ==============================================================================
 BOOST BY PYTHON                                       *vim-iced-install-python*