Type Alias Result<A, E>

A value which can be of either type A or type E.

This is normally used as a return value for operations which can fail: E is short for Error. A can be thought of as the success value, and E is the error value. This is reflected in their constructors: to construct a success value, you call Ok, and to construct an error value, you call Err.

You can also use the Result.await function to convert a Promise that could throw an exception into a Promise that won't throw but instead returns a Result containing either the error or the expected result, or the Result.try function to run a function and catch any exceptions into a Result return value.

See

• IResult for methods on Result objects
• Result for static methods in the Result namespace

Example

function processResult(result: Result<string, Error>): void {
    if (result.isOk()) {
        console.info(result.value);
    } else {
        console.error(result.value.message);
    }
}

processResult(Ok("Hello Joe!"));
processResult(Err(new Error("Get Robert to fix the bug!")));
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