True Myth / maybe / MaybeConstructor

Interface: MaybeConstructor

The public interface for the Maybe class as a value: a constructor and the associated static properties.

Constructors

Constructor

new MaybeConstructor<T>(value?): Maybe<T>

Parameters

value?

T | null

Returns

Maybe<T>

Properties

just()

just: {<F>(value): Maybe<F>; <T, F>(value): never; <F>(value): never; <T>(value): Maybe<T>; }

Call Signature

<F>(value): Maybe<F>

Create an instance of Maybe.Just.

Type Parameters

F

F extends (...args) => object

Parameters

value

F

The value to wrap in a Maybe.Just.

Returns

Maybe<F>

An instance of Maybe.Just<T>.

Throws

If you pass null or undefined.

Call Signature

<T, F>(value): never

Create an instance of Maybe.Just.

Type Parameters

T

T extends object

The type of the item contained in the Maybe.

F

F extends (...args) => T | null | undefined

Parameters

value

F

The value to wrap in a Maybe.Just.

Returns

never

An instance of Maybe.Just<T>.

Throws

If you pass null or undefined.

Call Signature

<F>(value): never

Create an instance of Maybe.Just.

Type Parameters

F

F extends (...args) => null | undefined

Parameters

value

F

The value to wrap in a Maybe.Just.

Returns

never

An instance of Maybe.Just<T>.

Throws

If you pass null or undefined.

Call Signature

<T>(value): Maybe<T>

Create an instance of Maybe.Just.

Type Parameters

T

T extends object

The type of the item contained in the Maybe.

Parameters

value

T

The value to wrap in a Maybe.Just.

Returns

Maybe<T>

An instance of Maybe.Just<T>.

Throws

If you pass null or undefined.

---

nothing()

nothing: <T>(_?) => Nothing<T>

Create an instance of Maybe.Nothing.

If you want to create an instance with a specific type, e.g. for use in a function which expects a Maybe<T> where the <T> is known but you have no value to give it, you can use a type parameter:

const notString = Maybe.nothing<string>();

Type Parameters

T

T extends object

The type of the item contained in the Maybe.

Parameters

_?

null

Returns

Nothing<T>

An instance of Maybe.Nothing<T>.

---

of()

of: {<F>(value): Maybe<F>; <T, F>(value): never; <F>(value): never; <T>(value): Maybe<T>; (value): Maybe<{ }>; }

Call Signature

<F>(value): Maybe<F>

Create a Maybe from any value.

To specify that the result should be interpreted as a specific type, you may invoke Maybe.of with an explicit type parameter:

const foo = Maybe.of<string>(null);

This is usually only important in two cases:

1. If you are intentionally constructing a Nothing from a known null or undefined value which is untyped.
2. If you are specifying that the type is more general than the value passed (since TypeScript can define types as literals).

Type Parameters

F

F extends (...args) => object

Parameters

value

F

The value to wrap in a Maybe. If it is undefined or null, the result will be Nothing; otherwise it will be the type of the value passed.

Returns

Maybe<F>

Call Signature

<T, F>(value): never

Create a Maybe from any value.

To specify that the result should be interpreted as a specific type, you may invoke Maybe.of with an explicit type parameter:

const foo = Maybe.of<string>(null);

This is usually only important in two cases:

1. If you are intentionally constructing a Nothing from a known null or undefined value which is untyped.
2. If you are specifying that the type is more general than the value passed (since TypeScript can define types as literals).

Type Parameters

T

T extends object

The type of the item contained in the Maybe.

F

F extends (...args) => T | null | undefined

Parameters

value

F

The value to wrap in a Maybe. If it is undefined or null, the result will be Nothing; otherwise it will be the type of the value passed.

Returns

never

Call Signature

<F>(value): never

Create a Maybe from any value.

To specify that the result should be interpreted as a specific type, you may invoke Maybe.of with an explicit type parameter:

const foo = Maybe.of<string>(null);

This is usually only important in two cases:

1. If you are intentionally constructing a Nothing from a known null or undefined value which is untyped.
2. If you are specifying that the type is more general than the value passed (since TypeScript can define types as literals).

Type Parameters

F

F extends (...args) => null | undefined

Parameters

value

F

The value to wrap in a Maybe. If it is undefined or null, the result will be Nothing; otherwise it will be the type of the value passed.

Returns

never

Call Signature

<T>(value): Maybe<T>

Create a Maybe from any value.

To specify that the result should be interpreted as a specific type, you may invoke Maybe.of with an explicit type parameter:

const foo = Maybe.of<string>(null);

This is usually only important in two cases:

1. If you are intentionally constructing a Nothing from a known null or undefined value which is untyped.
2. If you are specifying that the type is more general than the value passed (since TypeScript can define types as literals).

Type Parameters

T

T extends object

The type of the item contained in the Maybe.

Parameters

value

The value to wrap in a Maybe. If it is undefined or null, the result will be Nothing; otherwise it will be the type of the value passed.

T | null | undefined

Returns

Maybe<T>

Call Signature

(value): Maybe<{ }>

Create a Maybe from any value.

To specify that the result should be interpreted as a specific type, you may invoke Maybe.of with an explicit type parameter:

const foo = Maybe.of<string>(null);

This is usually only important in two cases:

1. If you are intentionally constructing a Nothing from a known null or undefined value which is untyped.
2. If you are specifying that the type is more general than the value passed (since TypeScript can define types as literals).

Parameters

value

unknown

The value to wrap in a Maybe. If it is undefined or null, the result will be Nothing; otherwise it will be the type of the value passed.

Returns

Maybe<{ }>