let data: DeepReadonly<ApiResponse>; data.user.settings.theme = "dark"; // Error: Cannot assign to 'theme'
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Date: April 14, 2026 Author: TypeScript Team / Community Spotlight ts playground 35
With , I clicked DeepReadonly<T[P]> and saw the recursive expansion — instantly clear why nested properties become readonly. Community Spotlight TS Playground 35 includes contributions from over 80 developers — from a one-line fix for Japanese IME support to the entire plugin system architected by a first-time OSS contributor. let data: DeepReadonly<ApiResponse>; data
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