ANN: ClojureScript 1.7.228 - parallel builds!

[David Nolen]

ClojureScript, the Clojure compiler that emits JavaScript source code.

README and source code: https://github.com/clojure/clojurescript

Leiningen dependency information:

    [org.clojure/clojurescript "1.7.228"]

The primary feature of this release is a new experimental compiler

flag - :parallel-build. If set to true the compiler will leverage

multiple threads to compile ClojureScript sources. Users have reported

signifant gains for cold development and production builds.

This release also includes a variety of small fixes and changes.

As always feedback welcome!

### Enhancements

* New experimental :parallel-build compiler option

### Changes

* CLJS-1538: Type hint some cljs.core predicates

* Docstring typos

* CLJS-1463: (js-debugger) should generate nil-returning expression

* CLJS-1516: better error message when calling macros with arity

* CLJS-1514: Remove Alpha designators on *-watch and ex-*

* clojure.core/require is not thread safe, use locks

* CLJS-1505: Add tests to characterize `type` and `instance?` behavior

* CLJS-1491: Check :source-map is boolean when :optimizations :none

* split sm/encode into 2 functions so JSON generation is optional

### Fixes

* CLJS-1539: Parallel compilation fails on circular dependencies

* CLJS-1425: self-host: cljs.js/eval cb argument inconsistent with docstring

* CLJS-1425: self-host: cljs.js/eval cb argument inconsistent with docstring

* CLJS-1524: Bad hashing for Cons

* CLJS-1487: Fix handling of timestamp comparison for dependencies in JARs

* CLJS-1498: Fix parallel build logging

* CLJS-1477: Do not attempt to resolve "native" type symbols

* CLJS-1236: `constructor` needs to munged if used as namespace segment

* CLJS-1330: self-host: .toString on int needs parens

* CLJS-1512: Self-host: arithmetic form meta missing :numeric

* CLJS-1506: doc for referred fn displays alias ns

* CLJS-1504: Self-host: Pseudo-namespace for macro namespace analysis

metadata

* CLJS-1483: Minor DCE regression with advanced compilation mode