es5-8

素颜马尾好姑娘i 2022-12-20 06:00 110阅读 0赞

ES5

*  保留关键字: `promise.catch(function() { });`

ES6

*  [箭头函数 Arrow functions][Arrow functions]: `<C onPress={() => this.setState({pressed: true})} />`
 *  [块级作用域 Block scoping][Block scoping]: `let greeting = 'hi';`
 *  [数组的扩展运算 Call spread][Call spread]: `Math.max(...array);`
 *  [类 Classes][Classes]: `class C extends React.Component { render() { return <View />; } }`
 *  [常量 Constants][Block scoping]: `const answer = 42;`
 *  [解构 Destructuring][Destructuring]: `var {isActive, style} = this.props;`
 *  [for...of][]: `for (var num of [1, 2, 3]) {}`
 *  [模块 Modules][Modules]: `import React, { Component } from 'react';`
 *  [动态属性键 Computed Properties][Computed Properties]: `var key = 'abc'; var obj = {[key]: 10};`
 *  对象方法的简写 Object Consise Method: `var obj = { method() { return 10; } };`
 *  [对象属性的简写 Object Short Notation][Computed Properties]: `var name = 'vjeux'; var obj = { name };`
 *  [参数的扩展运算 Rest Params][Rest Params]: `function(type, ...args) { }`
 *  [字符串模板 Template Literals][Template Literals]: ``var who = 'world'; var str = `Hello ${who}`;``

ES8

*  [参数列表末尾允许放置逗号 Function Trailing Comma][Function Trailing Comma]: `function f(a, b, c,) { }`
 *  [异步函数 Async Functions][Async Functions]: `async function doStuffAsync() { const foo = await doOtherStuffAsync(); };`

Stage 3

*  [对象的扩展运算 Object Spread][Object Spread]: `var extended = { ...obj, a: 10 };`
 *  [Optional Chaining][]: `var name = obj.user?.name;`

其他特性

*  [JSX][]: `<View style={ {color: 'red'}} />`
 *  [Flow][]: `function foo(x: ?number): string {}`
 *  [TypeScript][]: `function foo(x: number | undefined): string {};`
 *  [Babel Template][]: allows AST templating

##  ##

[Arrow functions]: http://babeljs.io/docs/learn-es2015/#arrows
[Block scoping]: https://babeljs.io/docs/learn-es2015/#let-const
[Call spread]: http://babeljs.io/docs/learn-es2015/#default-rest-spread
[Classes]: http://babeljs.io/docs/learn-es2015/#classes
[Destructuring]: http://babeljs.io/docs/learn-es2015/#destructuring
[for...of]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for...of
[Modules]: http://babeljs.io/docs/learn-es2015/#modules
[Computed Properties]: http://babeljs.io/docs/learn-es2015/#enhanced-object-literals
[Rest Params]: https://github.com/sebmarkbage/ecmascript-rest-spread
[Template Literals]: http://babeljs.io/docs/learn-es2015/#template-strings
[Function Trailing Comma]: https://github.com/jeffmo/es-trailing-function-commas
[Async Functions]: https://github.com/tc39/ecmascript-asyncawait
[Object Spread]: https://github.com/tc39/proposal-object-rest-spread
[Optional Chaining]: https://github.com/tc39/proposal-optional-chaining
[JSX]: https://zh-hans.reactjs.org/docs/jsx-in-depth.html
[Flow]: http://flowtype.org/
[TypeScript]: https://www.typescriptlang.org/
[Babel Template]: https://babeljs.io/docs/en/babel-template