Allow omitting the `as` clause in `each` statement

[hgiesel]

Describe the problem

It would be nice if we could forego the as part of an #each statement, if we don't need it.

Currently we have to write it like this.

This is probably a good first issue

Describe the proposed solution

Instead we could just write {#each param}{/each}

Alternatives considered

Just assign to _, as I have done above.

Importance

nice to have

[Prinzhorn]

Can you post an actual example where this would be needed? As this is much simpler written as:

<div style:width="{indent * 10}px" />

Even if there is such an example, I don't think it warrants the additional syntax. This is also a duplicate of #2968 because you just want to iterate N times. Such a #range block could arguably have ...as... be optional.

[hgiesel]

Closing in favor of #2968

[oscarhermoso]

@hgiesel Consider reopening this?

Now that Svelte 4 supports iterators, this could be the syntax for a range expression

{#each range(1, 5)}
  ...
{/each}

[hgiesel]

@oscarhermoso Sure! With the support for iterators, this makes a whole lot more sense than a new keyword

[Rich-Harris]

I think I like this idea. I'd want to be able to include the index in {#each Array(n), i}.

It's a small change, but it feels less messy and more intentional. It seems like there's a potential ambiguity with TypeScript (if there's only one as, could it mean a typecast?) but since you can only access the item if it's named, it's totally fine to stipulate that if there's only one as it's not a typecast.

Reasons not to do this:

• it's more syntax to learn
• it's possible that we'd want to overhaul each blocks in future, and this could feel churny

Having said that, #2968 is an extraordinarily popular feature request, and this seems like a better solution to that problem.