Describe the bug

I am pretty sure this is not necessarily a bug but an intended behaviour. However, the error given is so vague, and I could not find any documentation explaining why this functionality is not supported. Given is the following snippet:

<script lang="ts">
  import type { Snippet } from 'svelte';

  function formatter(v: number): ReturnType<Snippet<[number, string]>> {
    return draw(v, 'pink');
  }
</script>

{@render draw(0, 'orange')}

{@render formatter(0)} <!-- ERROR: Value is not a function error-->

{#snippet draw(value: number, color: string)}
  <p>
    value:
    <span style="background:{color}">
      {value}
    </span>
  </p>
{/snippet}

I try to create a new snippet that only takes part of an original snippet. Type wise this should be supported as draw has the following typing:

const draw: (value: number, color: string) => ReturnType<import("svelte").Snippet>

My expectation was that formatter would behave similarly to the following

{#snippet formatter(value: number)}
  {@render draw(value, 'pink')}
{/snippet}

The browser complains with a strange error which I have never encountered before. I suspect it has something to do with component mounting, unmounting or scoping? What part of Svelte magic am I missing in order to understand this error? Would this behaviour be possible with createRawSnippet?

Reproduction

https://svelte.dev/playground/33470f759ec0434cbcb597f5119a36da?version=5.2.11

Logs

No response

System Info

System:
    OS: macOS 15.1.1
    CPU: (8) arm64 Apple M1 Pro
    Memory: 146.22 MB / 32.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 22.2.0 - ~/.nvm/versions/node/v22.2.0/bin/node
    Yarn: 1.22.19 - /usr/local/bin/yarn
    npm: 10.7.0 - ~/.nvm/versions/node/v22.2.0/bin/npm
    pnpm: 9.14.4 - ~/Library/pnpm/pnpm
    bun: 1.1.8 - ~/.bun/bin/bun
  Browsers:
    Chrome: 131.0.6778.86
    Safari: 18.1.1
  npmPackages:
    svelte: ^5.0.0 => 5.1.16

Severity

annoyance