V8 5.1 发布了，V8 是 Google 发布的开源 JavaScript 引擎，采用 C++ 编写，在 Google 的 Chrome 浏览器中被使用。V8 引擎可以独立运行，也可以用来嵌入到 C++ 应用程序中执行。

以下是一些值得关注的内容：

ES6 & ES7 support

• Exponentiation operator

• This release contains support for the ES7 exponentiation operator, an infix notation to replace Math.pow.
  

• let n = 3**3; // n == 27
  n **= 2; // n == 729

• Evolving spec

• For more information on the complexities behind support for evolving specifications and continued standards discussion around web compatibility bugs and tail calls, see the V8 blog post ES6, ES7, and beyond.
  

Performance

V8 5.2 contains further optimizations to improve the performance of JavaScript built-ins, including improvements for Array operations like the isArray method, the in operator, andFunction.prototype.bind. This is part of ongoing work to speed up built-ins based on new analysis of runtime call statistics on popular web pages. For more information, see the V8 Google I/O 2016 talk and look for an upcoming blog post on performance optimizations gleaned from real-world websites.

V8 API

Please check out our summary of API changes. This document gets regularly updated a few weeks after each major release. 

Developers with an active V8 checkout can use 'git checkout -b 5.2 -t branch-heads/5.2' to experiment with the new features in V8 5.2. Alternatively you can subscribe to Chrome's Beta channel and try the new features out yourself soon.

详情：http://v8project.blogspot.com/2016/06/release-52.html

下载地址：https://chromium.googlesource.com/v8/v8/