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Svelte generation fails if there is an inner function

See original GitHub issue
  • I am interested in helping provide a fix!


  • This only impacts specific generators/outputs (please list them here): Svelte

Describe the bug

Mitosis fails with an error trying to generate Svelte output for a simple component with an inner function, in this case addItem()

import { useState } from '';

export interface State {
  list: string[];
  newItemName: string;

export default function MyComponent(props: any) {
  const state = useState<State>({
    list: ['hello', 'world'],
    newItemName: 'New item',

  function addItem() {
    state.list = [...state.list, state.newItemName];

  return (
        padding: '10px',

        class="shadow-md rounded w-full px-4 py-2"
        onChange={(event) => (state.newItemName =}

        class="bg-blue-500 rounded w-full text-white font-bold py-2 px-4"
          margin: '10px 0',
        onClick={(event) => addItem()}
        Add list item

      <ul class="shadow-md rounded">
        { => (
            class="border-gray-200 border-b"
              padding: '10px',

**To Reproduce**

Checkout current mainline.

Edit ``packages/e2e-app/mitosis.config.js` to un-comment svelte output

`yarn workspace run build`

Notably, if you remove the inner addItem function, Svelte output is generated.

**Expected behavior**

Generates (valid) Svelte

Alternatively, maybe such an inner function is considered invalid Mitosis? It work OK for React, Solid, Vue (at least)

Issue Analytics

  • State:closed
  • Created a year ago
  • Comments:6 (6 by maintainers)

github_iconTop GitHub Comments

samijabercommented, Jun 17, 2022

I’d rather stick with creating issues until we have that system in place, to avoid the risk of forgetting what to test for. I don’t mind having tons of issues highlighting bugs 😄

kylecordescommented, Jun 17, 2022

I think we can close this one because the ongoing improvement of the docs to set expectations of what code works is already well-known elsewhere, right?

Read more comments on GitHub >

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