/*---------------------------------------------------------------------------------------------
 *  Copyright (c) Microsoft Corporation. All rights reserved.
 *  Licensed under the MIT License. See License.txt in the project root for license information.
 *--------------------------------------------------------------------------------------------*/

export const memoizeLast = <A, T>(fn: (args: A) => T): ((args: A) => T) => {
  let last: { arg: A; result: T } | undefined;
  return arg => {
    if (last && last.arg === arg) {
      return last.result;
    }

    const result = fn(arg);
    last = { arg, result };
    return result;
  };
};
