REPL Options

ClojureScript REPLs can take nearly all the same options that can be supplied to cljs.closure/build, for details see Compiler Options. This page documents additional supported options.

• :analyze-path
• :def-emits-var
• :repl-requires
• :repl-verbose
• :watch
• :watch-fn

analyze-path

Sets a source path to analyze upon REPL initialization so that, if it connects to an already-running JavaScript environment, symbols for any previously loaded namespaces are available. May also be set to a vector of paths to analyze.

:analyze-path "src"

def-emits-var

Sets whether def (and derived) forms evaluated at the REPL return either a Var (if set to true) or the def init value (if false). Only affects forms evaluated at the REPL; compiled source behaves as if set to false. Default is true.

:def-emits-var false

repl-requires

Specifies a set of lib specs (per the require REPL special) to be automatically loaded when launching a REPL. Defaults to specs that refer doc etc. along with pp.

:repl-requires ['[cljs.repl :refer-macros [source doc find-doc apropos dir pst]]
                '[cljs.pprint :refer [pprint] :refer-macros [pp]]]

repl-verbose

Enable verbose reporting for the REPL. Useful for debugging. Defaults to false.

:repl-verbose true

This prints the compiled JavaScript before printing its evaluation:

cljs.user=> (+ 1 2)
((1) + (2))
3

watch

Watch a source directory for recompilation to avoid spinning up an additional JVM.

:watch "src"

watch-fn

:watch-fn (fn [] (println "built!"))

A function of no arguments to run after a successful build.