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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Clarity around getPersisted returning undefined","articleBody":"### Describe the bug\r\n\r\nHi. Thank you for a great project. I am working on another persister and stumbled onto a small issue.\r\n\r\nThe type of `createCustomPersister`'s [`getPersisted` parameter](https://github.com/tinyplex/tinybase/blob/2f3e053c6d4aba24e6568787f0e2b4caa23c7ebd/src/persisters/index.ts#L81) permits returning `Promise\u003cundefined\u003e`, but during the `load()` the type of returned value is coerced ([in `setContentOrChanges`](https://github.com/tinyplex/tinybase/blob/2f3e053c6d4aba24e6568787f0e2b4caa23c7ebd/src/persisters/index.ts#L151)) skipping the check for `undefined` which results in e.g. `store.setContent` failing like this:\r\n\r\n```\r\nGot TypeError: undefined is not iterable (cannot read property Symbol(Symbol.iterator))\r\n    at setContent (...../tinybase/5.0.3/index.js:2934:22)\r\n    at setContentOrChanges (...../tinybase/5.0.3/index.js:1223:28)\r\n    .....\r\n```","author":{"url":"https://github.com/wattroll","@type":"Person","name":"wattroll"},"datePublished":"2024-07-16T11:19:03.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":14},"url":"https://github.com/161/tinybase/issues/161"}