@kherge/result - v1.0.0

The given function is invoked within a try/catch block. If an error is caught, it is returned as an instance of Err. If no error is thrown, then the result is returned as an instance of Ok.

It is important to know that this function is unable to determine the proper type of the thrown error. While the type defaults to the built-in JavaScript Error type, it is very much encouraged that you specify the error type.

// A simple function that can throw an error.
const throws = (fail: boolean) => {
  if (fail) {
    throw new Error("An example error.");
  }

  return "example";
};

// An example of the error being caught.
let result: Result<string, Error> = attempt(() => throws(true));

assert(result.isErr() === true);

// An example of the result being returned.
result = attempt(() => throws(false));

assert(result.isOk() === true);

let result: Result<string, string> = err('error');

assert(result.isErr() === true);

This function provides a convenient way of wrapping the result of a function that could return null or undefined. If null or undefined is given, an instance of None is returned. If any other value is provided, including other falsy values, an instance of Some is returned.

let option: Option<string> = maybe(null);

assert(option.isNone() === true);

option = maybe("example");

assert(option.isSome() === true);

let option: Option<string> = none();

assert(option.isNone() === true);

let result: Result<string, string> = ok('value');

assert(result.isOk() === true);

let option: Option<string> = some('example');

assert(option.isSome() === true);