Default globals for strict mode

[NullVoxPopuli]

Propose default globals for strict mode

Rendered

Implementation:

• default globals implementation babel-plugin-ember-template-compilation#68

Summary

This pull request is proposing a new RFC.

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• The team believes the concepts described in the RFC should be pursued.
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• The RFC has a champion within one of the relevant teams.
• The RFC has consensus after the FCP period.

[bartocc]

This is not a direct comment about this RFC, but I did not realize globalThis was available inside strict mode templates! And as the RFC states, it must be pretty useful!

I guess an alternative to this RFC would at least be to update the documentation to help devs take advantage of this, with examples.

As far as I'm concerned, I'll start trying to tinker with globalThis.Array etc… asap!

[tcjr]

Over time, Ember has done a great job of eliminating hard-to-debug magic (implicit #each, implicit this, etc.) The templates, in particular, have become stricter and stricter. Still, popular addons, like ember-composable-helpers, had to do elaborate opt-in/opt-out build-time shenanigans to avoid global resolver issues. Now with full strict mode and the arrival of template tag, everything is imported and there are no surprises.

The motivation section of the RFC has the example:

const { JSON } = globalThis;

<template>
  {{JSON.stringify @data null 3}}
</template>

I may be alone on this island, but I like modern Ember's strictness and I think the above is a great way indicate intent and get support with just one line of code.

So, I guess I agree with @bartocc that showcasing the availability and ease of use of globalThis would be a pretty good non-code alternative.

[NullVoxPopuli]

why use globalThis for common things, when in every other js/ts file you don't need to?

[tcjr]

I dunno. I guess because the space inside a <template> tag isn't js/ts.

Feel free to completely disregard my opinion here. Of the list of things being added to the scope, I've only ever wished I had JSON. I realize I'm probably not qualified to comment since I've not encountered the UX burden this RFC is eliminating.