发布于 2015-08-05 00:22:08 | 149 次阅读 | 评论: 0 | 来源: 网友投递
IO.js 服务器端 JS 引擎
IO.js 是为 V8 引擎编写的基于事件 IO 的实现。io.js可以说是彻底从NodeJS里分离出来的一条分支。既然是分支，io.js便也基本兼容NodeJS的各种API，连执行指令也依旧兼容Node的 node XXX （新指令是 iojs XXX ）。不过io.js采纳了最新版本的V8引擎，并也将会时刻跟进V8的更新，也因此我们可以轻松地在io.js上抢先使用那些JavaScript ECMA-262规范上的新特性。
io.js 3.0.0 发布下载，主要更新内容如下：
buffer:
Due to changes in V8, it has been necessary to reimplement Buffer on top of V8's Uint8Array. Every effort has been made to minimize the performance impact, however Buffer instantiation is measurably slower. Access operations may be faster in some circumstances but the exact performance profile and difference over previous versions will depend on how Buffer is used within applications. (Trevor Norris) #1825.
Buffer can now take ArrayBuffers as a constructor argument (Trevor Norris) #2002.
When a single buffer is passed to Buffer.concat(), a new, copied Buffer object will be returned; previous behavior was to return the original Buffer object (Sakthipriyan Vairamani) #1937.
build: PPC support has been added to core to allow compiling on pLinux BE and LE (AIX support coming soon) (Michael Dawson) #2124.
dgram: If an error occurs within socket.send() and a callback has been provided, the error is only passed as the first argument to the callback and not emitted on the socket object; previous behavior was to do both (Matteo Collina & Chris Dickinson) #1796
freelist: Deprecate the undocumented freelist core module (Sakthipriyan Vairamani) #2176.
http:
Status codes now all use the official IANA names as per RFC7231, e.g. http.STATUS_CODES[414] now returns 'URI Too Long' rather than 'Request-URI Too Large' (jomo) #1470.
Calling .getName() on an HTTP agent no longer returns a trailing colon, HTTPS agents will no longer return an extra colon near the middle of the string (Brendan Ashworth) #1617.
node:
NODE_MODULE_VERSION has been bumped to 45 to reflect the break in ABI (Rod Vagg) #2096.
Introduce a new process.release object that contains a name property set to 'io.js' and sourceUrl, headersUrl and libUrl (Windows only) properties containing URLs for the relevant resources; this is intended to be used by node-gyp (Rod Vagg) #2154.
The version of node-gyp bundled with io.js now downloads and uses a tarball of header files from iojs.org rather than the full source for compiling native add-ons; it is hoped this is a temporary floating patch and the change will be upstreamed to node-gyp soon (Rod Vagg) #2066.
repl: Persistent history is now enabled by default. The history file is located at ~/.node_repl_history, which can be overridden by the new environment variable NODE_REPL_HISTORY. This deprecates the previous NODE_REPL_HISTORY_FILE variable. Additionally, the format of the file has been changed to plain text to better handle file corruption. (Jeremiah Senkpiel) #2224.
smalloc: The smalloc module has been removed as it is no longer possible to provide the API due to changes in V8 (Ben Noordhuis) #2022.
tls: Add server.getTicketKeys() and server.setTicketKeys() methods for TLS session key rotation (Fedor Indutny) #2227.
v8: Upgraded to 4.4.63.26
ES6: Enabled computed property names
ES6: Array can now be subclassed in strict mode
ES6: Implement rest parameters in staging, use the --harmony-rest-parameters command line flag
ES6: Implement the spread operator in staging, use the --harmony-spreadcalls command line flag
Removed SetIndexedPropertiesToExternalArrayData and related APIs, forcing a shift to Buffer to be reimplemented based on Uint8Array
Introduction of Maybe and MaybeLocal C++ API for objects which may or may not have a value.
Added support for PPC
详细内容请查看：更新日志。
下载地址：Source code (zip)
IO.js 是为 V8 引擎编写的基于事件 IO 的实现。io.js可以说是彻底从NodeJS里分离出来的一条分支。既然是分支，io.js便也基本兼容NodeJS的各种API，连执行指令也依旧兼容Node的 node XXX （新指令是 iojs XXX ）。不过io.js采纳了最新版本的V8引擎，并也将会时刻跟进V8的更新，也因此我们可以轻松地在io.js上抢先使用那些JavaScript ECMA-262规范上的新特性。