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Exporting as ES Module Syntax (ESM)

See original GitHub issue

Please, export "module" entry point in the package.json as ES Module Syntax (ESM).

More info about it here: https://www.pikapkg.com/about/

Issue Analytics

State:
Created 4 years ago
Reactions:8
Comments:21 (17 by maintainers)

Top GitHub Comments

5reactions

Splaktarcommented, Jul 18, 2020

I am running into this same issue with an app built using apollo-client. It gives this error with Angular CLI version 10:

WARNING in /Users/splaktar/Git/my-app/node_modules/zen-observable-ts/lib/bundle.esm.js depends on 'zen-observable'. CommonJS or AMD dependencies can cause optimization bailouts.
For more info see: https://angular.io/guide/build#configuring-commonjs-dependencies

https://angular.io/guide/build#configuring-commonjs-dependencies has some good links to explain why CommonJS modules don’t support tree shaking and how ES Modules work.

zen-observable-ts is importing correctly:

import zenObservable from 'zen-observable';

But due to the lacking "module": "esm.js", that ends up getting the CommonJS module (index.js) instead of the ES Module.

It looks like the approach in PR https://github.com/zenparsing/zen-observable/pull/74 should solve this and hopefully avoid any of the pitfalls that were faced in the past.

3reactions

zenparsingcommented, Oct 16, 2019

Sounds cool - I’ll give it a try.