Rationale for dropping ModuleImport syntax?

[Axel Rauschmayer]

Isn’t the problem, though, that default-exporting an object prevents static checking? It feels like an abuse of this feature to me.

With a ModuleImport statement, you have the choice between selectively importing items and importing everything as an object. With default-exporting an object, you don’t have that choice (you can work around this limitation, but still).

I do see your point, but I think module imports are useful when the contents of a module change relatively frequently and/or if there are many items in a module. In other words, I think that is something that will live on (justifiedly so) and should be supported properly.


On Jun 9, 2014, at 8:49 , Domenic Denicola <domenic at domenicdenicola.com> wrote:

> I am beginning to come around to the removal. It will just encourage module authors to use default exports exclusively (e.g. fs will default-export an object including readFile et al., instead of exporting multiple functions), which will put us squarely back in parity with the CommonJS/AMD systems, and ease migration.
>  
> If module authors try to use multi-exports, they will get upset users who wish to be able to do `import _ from "underscore"; _.zip(…)`, but cannot. So instead they will use default exports only, which does allow this familiar style.
>  
> In the end all of the non-default export forms, and the braced multi-import form, will just be relegated to the “bad parts” bin, and default exports and unbraced single-import will remain in the “good parts” bin, giving us the same CommonJS/AMD world we have today, but with some vestigial syntax unused by popular libraries.
>  
> From: es-discuss [mailto:es-discuss-bounces at mozilla.org] On Behalf Of Axel Rauschmayer
> Sent: Monday, June 9, 2014 02:39
> To: es-discuss list
> Subject: Rationale for dropping ModuleImport syntax?
>  
> Context: https://gist.github.com/caridy/eefb9b104874465d4e1c#1-moduleimport-syntax-importdeclaration
>  
> ```js
> module foo from "foo"; // drop this
> import bar from "bar";
> ```
>  
> I’m seeing the following contra against dropping ModuleImport syntax:
>  
> > Contra: without a way to access the module object, it is difficult to deal with modules with many exports (e.g.: underscore), but we could fix this by using a reflective API to access imported modules
>  
> Isn’t this a frequent use case? Which would lead to ugly and very inconsistent code, especially if multiple imports are involved. I also don’t see how CommonJS-style modules could be neatly migrated to ES6 modules if this feature was dropped.
>  
> I do agree that the ModuleImport reads a bit strange, but that could be fixed, e.g. via a suggestion I’ve seen somewhere:
>  
> ```js
> import module foo from "foo";
> ```
>  
> -- 
> Dr. Axel Rauschmayer
> axel at rauschma.de
> rauschma.de

-- 
Dr. Axel Rauschmayer
axel at rauschma.de
rauschma.de



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