Improve the TypeScript types

Author: sindresorhus

index.d.ts

@@ -1,16 +1,17 @@
-export type Reviver = (key: string, value: any) => any;
+export type Reviver = (this: unknown, key: string, value: unknown) => unknown;
 export type BeforeParse = (data: string) => string;
 
 export interface Options {
 	/**
 	 * Applies a function to the JSON string before parsing.
 	 */
-	beforeParse?: BeforeParse;
+	readonly beforeParse?: BeforeParse;
+
 	/**
 	 * Prescribes how the value originally produced by parsing is transformed, before being returned.
 	 * See the [`JSON.parse` docs](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/parse#Using_the_reviver_parameter) for more.
 	 */
-	reviver?: Reviver;
+	readonly reviver?: Reviver;
 }
 
 /**
@@ -20,12 +21,14 @@ export interface Options {
  *
  * @example
  *
- * import * as loadJsonFile from 'load-json-file';
+ * import loadJsonFile from 'load-json-file';
  *
- * const json = loadJsonFile.sync('foo.json');
- * //=> {foo: true}
+ * (async () => {
+ * 	const json = await loadJsonFile('foo.json');
+ * 	//=> {foo: true}
+ * })();
  */
-export function sync<T = unknown>(filePath: string, options?: Options): T;
+export default function loadJsonFile<T = unknown>(filePath: string, options?: Options): Promise<T>;
 
 /**
  * Read and parse a JSON file.
@@ -34,11 +37,9 @@ export function sync<T = unknown>(filePath: string, options?: Options): T;
  *
  * @example
  *
- * import loadJsonFile from 'load-json-file';
+ * import * as loadJsonFile from 'load-json-file';
  *
- * (async () => {
- * 	const json = await loadJsonFile('foo.json');
- * 	//=> {foo: true}
- * })();
+ * const json = loadJsonFile.sync('foo.json');
+ * //=> {foo: true}
  */
-export default function loadJsonFile<T = unknown>(filePath: string, options?: Options): Promise<T>;
+export function sync<T = unknown>(filePath: string, options?: Options): T;