feat(PersistedState): compile-time guard preventing undefined as a valid value in the stored type#411
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kraktus wants to merge 1 commit intosvecosystem:mainfrom
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feat(PersistedState): compile-time guard preventing undefined as a valid value in the stored type#411kraktus wants to merge 1 commit intosvecosystem:mainfrom
undefined as a valid value in the stored type#411kraktus wants to merge 1 commit intosvecosystem:mainfrom
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…valid value in the stored type `undefined` is already used internally by `PersistedState` as a special case to indicate that the value is not present in storage, and in case of deserialisation failure. This make using `undefined` in user-code a footgun, because for example `persistentState.current = undefined` is not working as expected, being a NOOP instead of emptying the state. While this is technically a breaking-change, I consider it a patch because the user-code impacted is buggy anyway. Alternatively another approach would be allow undefined state. A draft PR is available here: svecosystem#408. I did not get to the end of it, because the issue is that undefined has no valid JSON value, so it would require additional (de)serialisation logic, especially for custom ones.
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This was referenced Feb 27, 2026
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undefinedis already used internally byPersistedStateas a special case to indicate that the value is not present in storage, and in case of deserialisation failure.This make using
undefinedin user-code a footgun, because for examplepersistentState.current = undefinedis not working as expected, being a NOOP instead of emptying the state.While this is technically a breaking-change, I consider it a patch because the user-code impacted is buggy anyway.
Alternatively another approach would be allow undefined state. A draft PR is available here: #408. I did not get to the end of it, because the issue is that undefined has no valid JSON value, so it would require additional (de)serialisation logic, especially for custom ones.