Function 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:

const yayNumber = ok<number, string>(12);
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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>();
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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');
}
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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);
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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>();
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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');
}
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