Immutable.js 3.8.1 发布，不可变数据集合

Immutable.js 3.8.1 发布了，Immutable 是 Facebook 开发的不可变数据集合。不可变数据一旦创建就不能被修改，是的应用开发更简单，允许使用函数式编程技术，比如惰性评估。Immutable JS 提供一个惰性 Sequence，允许高效的队列方法链，类似 map 和 filter ，不用创建中间代表。

immutable 通过惰性队列和哈希映射提供 Sequence, Range, Repeat, Map, OrderedMap, Set 和一个稀疏 Vector。

新特性：

• The methods keyOf, findKey, lastKeyOf, and findLastKey were moved from KeyedIterable to Iterable, so they may be also used on Lists and Sets. (#740)

Bug 修复:

• Some issues with the flow definitions have been polished out thanks to @marudor. (#840, #841, #845)

• Collections which contain Symbol keys or values can now be stringified. (#620)

• Negative indexing into the keySeq of an IndexedIterable returns correct results. (#811)

• Can use the value Infinity as a key in a Collection without crashing. (#797)

下载地址：https://github.com/facebook/immutable-js/releases/tag/v3.8.1