Good observation. However, if I were to simplify, I’d only keep #3. #1 and #2 look more syntactically questionable to me (kind of abusing names as keywords/markers).
Axel
On 05 Dec 2013, at 15:18 , Kevin Smith <zenparsing at gmail.com> wrote:
> TLDR: We should consider deferring specialized syntax for exporting a "default" binding until after ES6.
>
> In the current draft, there are 3 ways to export a default binding:
>
> 1. Export a local binding with the name "default":
>
> class Parser { ... }
> export { Parser as default };
>
> 2. Use "default" as a BindingIdentifier. BindingIdentifer is parameterized on [Default]:
>
> export class default { ... }
>
> 3. Use a "default" assignment:
>
> export default class { ... }; // AssignmentExpression
>
> Methods 2 and 3 are inessential - they can be expressed in terms of 1.
>
> Methods 2 and 3 are minor optimizations. Method 1 is by no means painful to write or read.
>
> There are some potential downsides to providing methods 2 and 3:
>
> - It may be that they provide too many ways to do the same thing, with too little to differentiate them.
> - Method 2 makes the grammar more complex, for parsers and (more importantly) users.
> - Method 3, being an assignment, introduces initialization-order sensitivity that otherwise might be avoidable.
> - They bind orthogonal issues: On the one hand, the need to export a default binding, and on the other, the need to reference a local binding with some local name.
>
> Proposal: defer "default export" sugarings until ES7, when we can use data gathered from experience with ES6 modules to guide syntax additions.
>
>
> _______________________________________________
> es-discuss mailing list
> es-discuss at mozilla.org
> https://mail.mozilla.org/listinfo/es-discuss
--
Dr. Axel Rauschmayer
axel at rauschma.de
home: rauschma.de
twitter: twitter.com/rauschma
blog: 2ality.com
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domenic at domenicdenicola.com (2013-12-10T01:49:34.325Z)
Good observation. However, if I were to simplify, I’d only keep #3. #1 and #2 look more syntactically questionable to me (kind of abusing names as keywords/markers).
Good observation. However, if I were to simplify, I’d only keep #3. #1 and #2 look more syntactically questionable to me (kind of abusing names as keywords/markers). Axel On 05 Dec 2013, at 15:18 , Kevin Smith <zenparsing at gmail.com> wrote: > TLDR: We should consider deferring specialized syntax for exporting a "default" binding until after ES6. > > In the current draft, there are 3 ways to export a default binding: > > 1. Export a local binding with the name "default": > > class Parser { ... } > export { Parser as default }; > > 2. Use "default" as a BindingIdentifier. BindingIdentifer is parameterized on [Default]: > > export class default { ... } > > 3. Use a "default" assignment: > > export default class { ... }; // AssignmentExpression > > Methods 2 and 3 are inessential - they can be expressed in terms of 1. > > Methods 2 and 3 are minor optimizations. Method 1 is by no means painful to write or read. > > There are some potential downsides to providing methods 2 and 3: > > - It may be that they provide too many ways to do the same thing, with too little to differentiate them. > - Method 2 makes the grammar more complex, for parsers and (more importantly) users. > - Method 3, being an assignment, introduces initialization-order sensitivity that otherwise might be avoidable. > - They bind orthogonal issues: On the one hand, the need to export a default binding, and on the other, the need to reference a local binding with some local name. > > Proposal: defer "default export" sugarings until ES7, when we can use data gathered from experience with ES6 modules to guide syntax additions. > > > _______________________________________________ > es-discuss mailing list > es-discuss at mozilla.org > https://mail.mozilla.org/listinfo/es-discuss -- Dr. Axel Rauschmayer axel at rauschma.de home: rauschma.de twitter: twitter.com/rauschma blog: 2ality.com -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mail.mozilla.org/pipermail/es-discuss/attachments/20131205/3ecbd226/attachment-0001.html>