typedKeyValue.ts

/**
 * Creates a typed key-value pair object to work around TypeScript issue #13948.
 * This function preserves the literal type of the key in the resulting object type.
 *
 * @see [source](https://github.com/microsoft/TypeScript/issues/13948#issuecomment-1333159066)
 *
 * @example
 * const obj = createTypedKeyValue('userId', 123);
 * // obj has type: { userId: number } with literal key preservation
 *
 * @template K - The key type (must be a valid property key: string, number, or symbol)
 * @template V - The value type
 * @param key - The object property key
 * @param value - The value to associate with the key
 * @returns A strongly-typed object with the key-value pair
 */
export function createTypedKeyValue<const K extends PropertyKey, V>(
  key: K,
  value: V,
): {[P in K]: {[Q in P]: V}}[K] {
  return {[key]: value} as any
}

/**
 * Type utility that represents a key-value pair with preserved literal key types.
 * Used as part of the TypeScript workaround for issue #13948.
 *
 * @template K - The key type (must be a valid property key: string, number, or symbol)
 * @template V - The value type
 */
export type TypedKeyValue<K extends PropertyKey, V> = {
  [P in K]: {[Q in P]: V}
}