expectErr

function ResultAsync.expectErr(
    result: AwaitableResult<T, E>,
    message: string
): Promise<E>

Unwraps the Err value from the result. If the result is an Ok, throws a ResultError with the given message.

Example

data-first

await ResultAsync.expectErr(err("fail"), "Expected an error");
// "fail"

await ResultAsync.expectErr(ok(5), "Expected an error");
// throws ResultError("Expected an error")

data-last

await pipe(err("fail"), ResultAsync.expectErr("Expected an error"));
// "fail"