0.0-3058 - Enhanced REPLs, faster compile times

Mar 9, 2015 by David Nolen on Google Groups

This is a significant enhancement release around REPLs and compile times.

All builtin REPLs (Nashorn, Node.js, Rhino and the browser REPL) now support the helper functions normally available via clojure.repl, these include: doc, find-doc, apropos, dir, source, and pst. All of the builtins REPL now also support source mapped stacktraces.

This release also includes many enhancements around compile times.

ClojureScript now ships with a default :optimizations setting of :none. Implicit now when using :none is source map generation and analysis caching. Analysis caching significantly speeds up compile times.

The standard library (cljs.core) is now AOTed compiled to JavaScript along with an AOTed analysis dump and an AOTed source map. This dramatically cuts down on cold start compile times. The standard library is never actually ever analyzed or compiled in your own builds. The result is particularly dramatic for REPLs.

ClojureScript is also now available for the first time as a standalone AOTed JAR. The Quick Start introduction has been rewritten in terms of the standalone JAR: https://github.com/clojure/clojurescript/wiki/Quick-Start

The new Quick Start is essential reading even if you are a relatively experienced ClojureScript developer.

As usual feedback welcome!



  • browser REPL source mapping for Firefox, Safari, Chrome
  • macro support in REPL special functions
  • CLJS-897: AOT core.cljs CLJS-899: AOT cache core.cljs analysis
  • CLJS-1078: Nashorn REPL should use persistent code cache
  • CLJS-1079: add way to execute arbitrary fn upon watch build completion
  • CLJS-1034: Support REPL-defined functions in stacktrace infrastructure
  • source mapping for Rhino
  • CLJS-1071: support symbol keys in :closure-defines
  • CLJS-1014: Support Closure Defines under :none
  • CLJS-1068: node target define
  • CLJS-1069: Generic :jsdoc support
  • CLJS-1030: add cljs.repl/pst
  • add cljs.repl/apropos, cljs.repl/find-doc, cljs.repl/dir
  • fix cljs.analyzer.api/all-ns docstring
  • add cljs.analyzer.api/ns-publics
  • CLJS-1055: cljs.repl/doc should support namespaces and special forms
  • Add ClojureScript special form doc map
  • CLJS-1054: add clojure.repl/source functionality to cljs.repl
  • CLJS-1053: REPLs need import special fn


  • move :init up in cljs.repl/repl
  • CLJS-1087: with-out-str unexpectedly affected by print-newline
  • CLJS-1093: Better compiler defaults
  • Bump deps latest Closure Compiler, Rhino 1.7R5, data.json 0.2.6, tool.reader 0.8.16
  • more sensible error if cljs.repl/repl arguments after the first incorrectly supplied
  • default REPLs to :cache-analysis true
  • default :output-dir for Nashorn and Node REPLs
  • change ES6 Map get support to take additional not-found parameter
  • deprecate clojure.reflect namespace now that REPLs are significantly enhanced, static vars, etc.


  • stop blowing away cljs.user in browser REPL so REPL fns/macros remain available
  • CLJS-1098: Browser REPL needs to support :reload and :reload-all
  • CLJS-1097: source map url for AOTed cljs.core is wrong
  • CLJS-1094: read option not used by cljs.repl/repl*
  • CLJS-1089: AOT analysis cache has bad :file paths
  • CLJS-1057: Nashorn REPL should not use EDN rep for errors
  • CLJS-1086: Keyword constants should have stable names
  • CLJS-964: Redefining exists? does not emit a warning like redefining array? does.
  • CLJS-937: local fn name should be lexically munged
  • CLJS-1082: analysis memoization bug
  • CLJS-978: Analysis caching doesn't account for constants table
  • CLJS-865: remove cljs.js-deps/goog-resource hack
  • CLJS-1077: analyze-deps infinite recursive loop
  • manually set *e in Rhino on JS exception
  • REPL options merging needs to be more disciplined
  • CLJS-1072: Calling .hasOwnProperty("source") in Clojurescript's string/replace will break with ES6
  • CLJS-1064: ex-info is not printable
  • Fix REPLs emitting code into .repl directory
  • CLJS-1066: Rhino REPL regression
  • be more disciplined about ints in murmur3 code
  • Node.js REPL should work even if :output-dir not supplied
  • Nashorn environment doesn't supply console, setup printing correctly

API Additions

including pre-releases 0.0-3053, 0.0-3030, 0.0-2985