Rebel - a command line REPL UI

The REPL is the environment in which all Clojure code runs, whether that be during development, testing and production systems.

rebel is a REPL UI that provides auto-completion, function call syntax help, themes and key binding styles to enhance the development experience. Clojure tools also include a REPL with a minimal interface by default.

Clojure REPL rebel readline - example of autocompletion

Install rebel readline

practicalli/clojure-deps-edn GitHub repository contains an alias for rebel readline. Fork and clone this repository to ~/.clojure to include the rebel alias and many other useful aliases.

If using your own ~/.clojure/deps.edn configuration, add an alias called :rebel

  1. :rebel {:extra-deps {com.bhauman/rebel-readline {:mvn/version "0.1.4"}}
  2.         :main-opts  ["-m" "rebel-readline.main"]}

Starting a rebel REPL

Start a Clojure REPL with Rebel Readline

  1. clojure -A:rebel

A REPL prompt displays and will evaluate code entered.

Clojure REPL rebel readline

Help at the REPL

rebel readline provides tools to help you discover and use functions from clojure.core and any other libraries you add to the REPL.

:repl/help will show all the commands available for rebel readline

TAB to autocomplete the current characters into a function name. All functions that match the characters will be show, allowing quick discovery of functions available. Typing in the first few characters of a function and press

Clojure REPL rebel readling - autocompletion

Moving the cursor after the name of a function will show the signatures available, so the correct arguments can be used with the function call.

Clojure REPL rebel readline - function signature help

Ctrl-x Ctrl-D or using the function clojure.repl/doc function will show the documentation for functions, so you can understand the functions purpose.

Clojure REPL rebel readline - doc function showing a function docstring

rebel commands

Type :repl/help or :repl TAB to see a list of available commands.

Keybinding Description
:repl/help Prints the documentation for all available commands.
:repl/key-bindings search or list current key bindings
:repl/quit Quits the REPL
:repl/set-color-theme Change the color theme :dark-screen-theme :light-screen-theme
:repl/set-key-map Change key bindings to given key-map, :emacs :vicmd :viins
:repl/toggle-color Toggle ANSI text coloration on and off
:repl/toggle-completion Toggle the completion functionality on and off
:repl/toggle-eldoc Toggle the auto display of function signatures on and off
:repl/toggle-highlight Toggle readline syntax highlighting on and off
:repl/toggle-indent Toggle the automatic indenting of Clojure code on and off

Key-bindings

Keybinding Description
Ctrl-C aborts editing the current line
Ctrl-D at the start of a line => sends an end of stream message
TAB word completion or code indent when cursor in whitespace at the start of line
Ctrl-X_Ctrl-D Show documentation for word at point
Ctrl-X_Ctrl-S Show source for word at point
Ctrl-X_Ctrl-A Show apropos for word at point
Ctrl-X_Ctrl-E Inline eval for SEXP before the point

Examine key-bindings with the :repl/key-bindings command.