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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:

ts
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:

ts
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:

ts
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:

ts
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:

ts
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 ​

T | null | undefined

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<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:

ts
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<{ }>