@jdeurt/maybe

An implementation of the Maybe monad in Typescript.

Installation

To install, run:

yarn add @jdeurt/maybe

API Documentation

Class: Maybe<A>

Maybe<A> is an abstract class that represents a type that may either hold a value of type A (represented as Just<A>) or not (represented as Nothing<A>).

Static Method: of

Creates a new Maybe<A> instance.

Static Method: nothing

Creates a new Nothing<A> instance.

Static Method: just

Creates a new Just<A> instance.

Method: isNothing

Returns true if the Maybe<A> instance is Nothing<A>, false otherwise.

Method: isJust

Returns true if the Maybe<A> instance is Just<A>, false otherwise.

Method: map

Transforms the value in the Just<A> using the function, if the Maybe<A> is Just<A>. If the Maybe<A> is Nothing<A>, does nothing.

Method: flatMap

Similar to map, but the provided function should return a Maybe<B> instance.

Method: apply

Applies the function contained in the Maybe<A> to another Maybe<A>, if both Maybe<A> instances are Just<A>. If either Maybe<A> is Nothing<A>, does nothing.

Method: equals

Checks if two Maybe<A> instances are equal.

Method: getOrElse

If the Maybe<A> instance is Just<A>, returns its value, otherwise returns the default value.

Method: orElse

If the Maybe<A> instance is Just<A>, returns it, otherwise returns Just<A> of the default value.

Method: get

Returns the value of the Maybe<A> instance if it's Just<A>, otherwise throws an error.

Method: toString

Returns the string representation of the Maybe<A> instance.

Class: Nothing<A>

Nothing<A> is a class that represents the absence of a value. It extends Maybe<A>.

Static Method: of

Creates a new Nothing<A> instance.

Class: Just<A>

Just<A> is a class that represents the presence of a value. It extends Maybe<A>.

Static Method: of

Creates a new Just<A> instance.