我想写一个泛型函数，使用类型安全函数返回布尔属性的值，但最终编译器告诉我他不识别我的值的类型。

type KeyOfType<T, V> = keyof {
  [P in keyof T as T[P] extends V ? P : never]: any
}

function getBooleanValue<T, K extends KeyOfType<T, boolean>>(obj: T, propName: K): boolean {
  return obj[propName]
//         ^
// Type 'T[K]' is not assignable to type 'boolean'.
//   Type 'T[keyof { [P in keyof T as T[P] extends boolean ? P : never]: any; }]' is not assignable to type 'boolean'.
//     Type 'T[string] | T[number] | T[symbol]' is not assignable to type 'boolean'.
//       Type 'T[string]' is not assignable to type 'boolean'.(2322)
}

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如果可能的话，我想避免将其转换为obj[propName] as unknown as boolean。
谢谢你的帮助！
编辑，因为缺少上下文：此操作是在泛型函数中完成的

type KeyOfType<T, V> = keyof {
  [P in keyof T as T[P] extends V ? P : never]: any
}

export function compareByBooleanProperty<T, K extends KeyOfType<T, boolean>>(
  propName: K,
): (a: T, b: T) => number {
  const propertyAccessor = (obj: T) => obj[propName]
  const booleanComparator =  compareBooleans
  return (a: T, b: T) => {
    const aValue = propertyAccessor(a)
    const bValue = propertyAccessor(b)
    return booleanComparator(aValue, bValue)
//                            ^
// Type 'T[K]' is not assignable to type 'boolean'.
//   Type 'T[keyof { [P in keyof T as T[P] extends boolean ? P : never]: any; }]' is not assignable to type 'boolean'.
//     Type 'T[string] | T[number] | T[symbol]' is not assignable to type 'boolean'.
//       Type 'T[string]' is not assignable to type 'boolean'.(2322)
  }
}

function compareBooleans(a: boolean, b: boolean): number {
  // algorithm
  return 0
}

type Person = {
  name: string
  isMarried: boolean
}

compareByBooleanProperty<Person, "isMarried">("isMarried") // comparator function by

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