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ES6 Module Consumption

See original GitHub issue

When attempting you use a modern bundler (in my case its Rollup http://rollupjs.org/). I cannot import individual modules that I need because they aren’t exported correctly.

Module MY_PROJECT/node_modules/web3-provider-engine/subproviders/rpc.js does not export default (imported by MY_PROJECT/lib/index.js)

Error: Module MY_PROJECT/node_modules/web3-provider-engine/subproviders/rpc.js does not export default (imported by MY_PROJECT/lib/index.js)

at Module.trace (MY_PROJECT/node_modules/rollup/src/Module.js:683:30)
at MY_PROJECT/node_modules/rollup/src/Module.js:265:30
at Array.forEach (native)
at MY_PROJECT/node_modules/rollup/src/Module.js:263:25
at Array.forEach (native)
at Module.bindReferences (MY_PROJECT/node_modules/rollup/src/Module.js:256:19)
at MY_PROJECT/node_modules/rollup/src/Bundle.js:104:44
at Array.forEach (native)
at MY_PROJECT/node_modules/rollup/src/Bundle.js:104:18

Issue Analytics

State:
Created 7 years ago
Comments:6 (2 by maintainers)

Top GitHub Comments

2reactions

BennyMcommented, May 29, 2017

Ok got it to work using the following syntax in my code:

import * as Web3ProviderEngine  from 'web3-provider-engine';
import * as RpcSource  from 'web3-provider-engine/subproviders/rpc';
import * as HookedWalletSubprovider from 'web3-provider-engine/subproviders/hooked-wallet';

0reactions

BennyMcommented, May 28, 2017

I’m using Webpack instead of rollup and am also experiencing difficulties. After importing

import { Web3ProviderEngine } from 'web3-provider-engine';

and creating an object

var engine = new Web3ProviderEngine();

I get the error: Web3ProviderEngine is not a constructor function.

The generated javascript looks like this:

var engine = new web3_provider_engine_1.Web3ProviderEngine();

While poking around in the browser I can find the function at the prefix.

Not sure if this is a webpack issue or the way the library is structured. I don’t experience this issue with for instance web3 or eth-lightwallet.

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