See question title. I found a great reference for the forms of export
available, but I have not seen what I'm looking for.
Is it possible to do something like the following?
// file: constants.js
export const SomeConstant1 = 'yay';
export const SomeConstant2 = 'yayayaya';
// file: index.js
export * as Constants from './constants.js';
Ie this would provide a named export Constants
inside of index.js
containing all of the named exports from constants.js
.
This answer seems to indicate it's not possible in TypeScript; is the same true for pure JavaScript?
(This example is a bit contrived; in reality I'm trying to have a prop-types.js
module that uses named exports for internal use within the React package, but also exports the prop type definitions under PropTypes
for external consumption. I tried to simplify for the sake of the question.)
No, it's not allowed in JS either, however there is a proposal to add it . For now, just use the two-step process with importing into a local variable and exporting that:
// file: constants.js
export const SomeConstant1 = 'yay';
export const SomeConstant2 = 'yayayaya';
// file: index.js
import * as Constants from './constants.js';
export {Constants};
2019 年的今天, 现在成为可能。
export * as name1 from …;
The proposal for this spec has merged to ecma262. If you're looking for this functionality in an environment that is running a previous JS, there's a babel plugin for it! After configuring the plugin (or if you're using ecma262 or later), you are able to run the JS in your question:
// file: constants.js
export const SomeConstant1 = 'yay';
export const SomeConstant2 = 'yayayaya';
// file: index.js
export * as Constants from './constants.js';
// file: component.js
import { Constants } from './index.js';
const newVar = Constants.SomeConstant1; // 'yay'
// file: index.js
// note, this doesn't have to be at the top, you can put it wherever you prefer
import * as AllExportsFromThisModule from "./index.js"; // point this at the SAME file
export default AllExportsFromThisModule;
export const SOME_CONSTANT = 'yay';
export const SOME_OTHER_CONSTANT = 'yayayaya';
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