Alternative to 'import * as' module syntax

This is no longer valid JavaScript:

import * as cosmiconfig from 'cosmiconfig';

cosmiconfig('module-name');

https://stackoverflow.com/questions/39415661/what-does-resolves-to-a-non-module-entity-and-cannot-be-imported-using-this/39415662#39415662

An ES6 module namespace object cannot be invoked as a function or with new. The thing you import using * as X from a module is defined to only have properties.

As a backwards-compatible change, this module should have something like this added at the bottom of src/index.js:

cosmiconfig.cosmiconfig = cosmiconfig;

That way we’ll be able to do this:

import { cosmiconfig } from 'cosmiconfig';

cosmiconfig('module-name');

It’s a bit silly. A default export is doable too, but as an external TypeScript user, I find it inconvenient to have a separate import syntax and/or group for importing this one function verses any associated types the type definitions also export.

[k2snowman69]

Not to be a stickler but Typescript (from their documentation) highly recommends that you move over to using the esModuleInterop solution… From their documentation:

Note: The new behavior is added under a flag to avoid unwarranted breaks to existing code bases. We highly recommend applying it both to new and existing projects. For existing projects, namespace imports (import * as express from "express"; express();) will need to be converted to default imports (import express from "express"; express();)

The reason for this is the old import * as syntax does go against the tc39 spec.

I don’t disagree that this won’t make typescript user’s lives easier in the short term but if added, in the long term you’ll likely just end up reverting the PR in the future anyways.

I’d say the better solution for your project is to upgrade to using the esModuleInterop (I just did this across my codebases, its a simple search and replace of import * as with import).

Merging the PR doesn’t impact me at all, more just wanted to let you know that long term the import * as syntax will likely be deprecated and removed in future versions of typescript so if you’re writing new code with it, probably want to just fix it now.

[davidtheclark]

You’re right, @JoshuaKGoldberg, that this is ES module syntax; but the aversion to a default export seems specific to TypeScript? I think a default export is fine and standard, so I’m not sure why it would become an issue for people using ES modules. I’d rather not make API changes to accommodate preferences like this, as long as the current API does work fine.