Eliminate unnecessary `if` statements

[benmccann]

Describe the problem

Consider the following code:

{#if iconData}
	{#if iconData.paths}
		{#each iconData.paths as path}
			<path {...path} />
		{/each}
	{/if}
{/if}

It could be rewritten as:

{#each iconData?.paths || [] as path}
	<path {...path} />
{/each}

This will save a larger amount of code than what is written in the source because the Svelte compiler must generate about ten lines for each if statement. At the very least it shouldn't be too hard to combine consecutive if statements into a single if statement

This example is from a real project: RobBrazier/svelte-awesome#1058

Describe the proposed solution

Implement it as an optimization in the compiler

Alternatives considered

Document it (possibly at https://kit.svelte.dev/docs/performance) and make users handle it themselves

Importance

nice to have

[adiguba]

Hello.

This is already possible in svelte 4 !
And in svelte 5 you can also omit the || [] :

REPL

[Conduitry]

Yes, you can already write code like this. The suggestion here is to add this as a compiler optimization.

[adiguba]

Oh sorry I don't understand your request...

[Zachiah]

Are you guys open to me taking a look at this and making a PR?