{#each} block does not work with Set()

[ahopkins]

Describe the bug
The {#each}{/each} expression does not operate on a Set().

Logs

RangeError: invalid array length

To Reproduce

See example here

In the above link, it works as expected. At the very end there is an {#each}{/each} block that has been commented out. If you uncomment that block you will see the error in the console.

Expected behavior

To loop thru thru the set object (perhaps by calling forEach) the same way it would thru an array.

Information about your Svelte project:

Browser: Firefox Developer Edition 68.0b2 (64-bit)
OS:

Distributor ID:	Arch
Description:	Arch Linux
Release:	rolling
Codename:	n/a

Svelte: "svelte": "^3.0.0" with "rollup-plugin-svelte": "^5.0.3",

Severity

Annoying and slightly unexpected. Seems like a potential minor fix. But there is a workaround.

{#each [...$pageloader.active] as call}
    - {call}<br />
{/each}

[Conduitry]

Duplicate of #3225 - this is intentionally not a feature.