docs(state): clarify observable() input is the underlying data#59
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sgup wants to merge 1 commit intoLegendApp:mainfrom
Open
docs(state): clarify observable() input is the underlying data#59sgup wants to merge 1 commit intoLegendApp:mainfrom
sgup wants to merge 1 commit intoLegendApp:mainfrom
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Adds a third sub-section under "Observables are mutable" explaining that the value passed to observable() is not cloned — it becomes the underlying data and is mutated in place as fields are updated. Calls out the most common gotcha (reusing a shared initialState constant as a reset target — the constant becomes structurally equal to the current state, so set() is a no-op via deep-equality) and shows the factory pattern as the fix. Refs LegendApp/legend-state#647 — when investigating that issue I audited my own codebase and found 8 stores with silently broken reset functions from this exact pattern. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>
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Adds a third sub-section under "Observables are mutable" on the Observable page, explaining that the value passed to
observable()is not cloned — it becomes the underlying data and is mutated in place as fields are updated.The existing section #1 covers the symptom ("set it back onto the observable, that just sets it to itself") but doesn't connect it back to the original input. The new sub-section calls out the most common pitfall — reusing a shared
initialStateconstant as a reset target — and shows the factory pattern as the fix.Refs LegendApp/legend-state#647 — when investigating that issue I audited my own codebase and found 8 stores with silently broken reset functions from this exact pattern.
No structural changes to the page — just a new sub-section appended to the existing list.
Disclosure: written together with Claude (Anthropic). Verified locally.