Utility methods in Typescript

Typescript-utils.ts

export const isPropAvailable = <T extends object>(
  inputObject: T,
  prop: string
): null | T[keyof T] => {
  if (typeof inputObject !== "object") return null;
  if (prop in inputObject) return inputObject[prop];
  return null;
};

export const deepNullCheck = <T extends object>(
  inputObject: T,
  propsToCheck: string[] | string
) => {
  if (typeof propsToCheck === "string")
    return isPropAvailable(inputObject, propsToCheck);
  return propsToCheck.reduce((prev: object, accu) => {
    return isPropAvailable(prev, accu);
  }, inputObject);
};

export const omitProps = <T extends object>(obj: T, arr: (keyof T)[]) =>
  Object.keys(obj).reduce(
    (prev, curr) =>
      arr.includes(curr as keyof T) ? prev : { ...prev, [curr]: obj[curr] },
    {}
  );