Script is:inline clarifications

[Jutanium]

What kind of changes does this PR include?

• New or updated content

Description

• To address Add: Explain how to run a function inside an inline script after the dom is loaded  #1407, explain that defer and similar attributes don't work on inlined scripts
• Explain why define:vars implies is:inline.

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[yanthomasdev]

LGTM! Nice job 🙌

[Jutanium]

Note to self: clarify that type=module protects the scope of a script, so you need to use is:inline to add something to the global scope

[delucis]

LGTM Dan — just left a suggestion.

Note to self: clarify that type=module protects the scope of a script, so you need to use is:inline to add something to the global scope

On this, it is possible to add to the global scope explicity from a type=module script, but it’s generally considered bad practice because of the async nature of modules (if you can’t control when each script runs, depending on globals across scripts is recipe for trouble).

<!-- Astro bundles this into a type="module" script -->
<script>
window.foo = 'some global value';
</script>

<!-- equivalent inline version -->
<script is:inline>
var foo = 'some global value';
</script>

Basically both of these should be avoided 😅

[tony-sull]

lgtm! Nicely done explaining this clearly without going deep into the weeds 👍

[Jutanium]

Everyone reviewed and approved this one, so I'm going to merge and bring any additional changes (regarding the module limitations) to a future PR!

@delucis I'm okay with the wordiness of the bundling explanation for now as it's in an advanced aside, but I may revisit it in that PR.