Create an instance of Ok.
If you need to create an instance with a specific type (as you do whenever you are not constructing immediately for a function return or as an argument to a function), you can use a type parameter:
const yayNumber = ok<number, string>(12);
Note: passing nothing will produce a Result<void, E>, passing undefined will
produce a Result<undefined, E> which is compatible with Result<void, E>.
const normalResult = ok<number, string>(42);
const explicitUndefined = ok<undefined, string>(undefined);
const implicitVoid = ok<void, string>();
In the context of an immediate function return, or an arrow function with a single expression value, you do not have to specify the types, so this can be quite convenient.
const arrowValidate = (data: SomeData): Result<void, string> =>
isValid(data) ? ok() : err('something was wrong!');
function fnValidate(data: someData): Result<void, string> {
return isValid(data) ? ok() : err('something was wrong');
}
The type of the error contained in the Result for the failure case
The value to wrap in a Result.Ok.
Create an instance of Ok.
If you need to create an instance with a specific type (as you do whenever you are not constructing immediately for a function return or as an argument to a function), you can use a type parameter:
Note: passing nothing will produce a
Result<void, E>, passingundefinedwill produce aResult<undefined, E>which is compatible withResult<void, E>.In the context of an immediate function return, or an arrow function with a single expression value, you do not have to specify the types, so this can be quite convenient.