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| type InferValue<Prop extends PropertyKey, Desc> = Desc extends { get(): any; value: any } ? never : Desc extends { value: infer T } ? Record<Prop, T> : Desc extends { get(): infer T } ? Record<Prop, T> : never;
type DefineProperty<Prop extends PropertyKey, Desc extends PropertyDescriptor> = Desc extends { writable: any; set(val: any): any; } ? never : Desc extends { writable: any; get(): any } ? never : Desc extends { writable: false } ? Readonly<InferValue<Prop, Desc>> : Desc extends { writable: true } ? InferValue<Prop, Desc> : Readonly<InferValue<Prop, Desc>>;
function defineProperty< Obj extends object, Key extends PropertyKey, PDesc extends PropertyDescriptor >(obj: Obj, prop: Key, val: PDesc): asserts obj is Obj & DefineProperty<Key, PDesc> { Object.defineProperty(obj, prop, val); }
const storage = { currentValue: 0 };
defineProperty(storage, 'maxValue', { value: 9001, writable: false });
storage.maxValue = 100;
|