Skip to content

Latest commit

 

History

History
86 lines (73 loc) · 2.61 KB

README.md

File metadata and controls

86 lines (73 loc) · 2.61 KB
Raw

Spartan REPL

A Clojure REPL hooked up to vanilla Vim in two lines of code. No (Spac)Emacs, no Cider, no fireplace.

spar•tan
(noun)

a Canadian dessert apple of a variety with crisp white flesh and maroon-flushed yellow skin.

Requirements

VIM (vanilla) Clojure >= 1.8 (CLI or lein both work)

Socket REPL

Clojure 1.8 introduced the ability for any arbitrary clojure program to have a socket REPL that can be externally switched on via a JVM opt flag:

;; $HOME/.clojure/deps.edn
{:aliases
  {
    ,,,
    :socket {:jvm-opts ["-Dclojure.server.repl={:port,50505,:accept,clojure.core.server/repl}"]}
    ,,,
  }
}

Alternatively for Leiningen:

;; $HOME/.lein/profiles.clj
{
  :user {:aliases {,,,
                   :jvm-opts ["-Dclojure.server.repl={:port,50505,:accept,clojure.core.server/repl}"]
                   ,,,
  }}
}

Configuring VIM

Save this macro in your VIMRC (optionally bound to p) then highlight the expression(s) you want to send to the repl and invoke the macro.

" this is not very paste friendly...
" ^M is return
" ^] is ESC
"$HOME/.vimrc
let @p = '"1ygg0"2y3w:new^M"2pa)^M^["1p:% ! nc -N localhost 50505^M'

What this does:

  • yank the selected code to register 1
  • move to the top of the current file you are in (NOTE: this assumes your ns declaration is on line 1)
  • yank until the end of your namespace name to register 2
  • create a fresh unnamed buffer
  • paste the namespace declaration and close it
  • paste your copied code to be evaluated
  • pipe the entire contents of your buffer to your repl (via netcat on port 50505)

Tying it all together

  • Create a fresh REPL by using either:
lein repl # by default user profile will be merged in via lein
# or
clojure -A:socket # use the global socket alias which turns on the socket repl
  • in your repl navigate to the sparta namespace:
(ns spartan-repl.sparta)
  • this namespace should be empty, test it via:
madness?
  ;; Syntax error compiling at (REPL:0:0).
  ;; Unable to resolve symbol: madness? in this context
  • over in sparta.clj evaluate the code within the comment block using the @p macro
  • your REPL session should now have madness? bound
madness?
;;=> :THIS-IS-SPARTA!

Limitations

  • anything preceding the namespace declaration - don't do it 🙂 what did you expected from a 2 line hack?