Maybe
This is a small library for handling potentially undefined values in TypeScript.
Api
import * as Maybe from '@katis/maybe'
const value: string | undefined = 'defined'
// map (or its alias mapDefined)
const length: number | undefined = Maybe.map(value, s => s.length)
// filter (or its alias filterDefined)
const shortString: string | undefined = Maybe.filter(value, s => s.length <= 3)
// orNull
const nullable: string | null = Maybe.orNull('nullable')
// fromNullable
const undefinedString: string | undefined = Maybe.fromNullable(nullable)
// getOrThrow
const neverReached: string = Maybe.getOrThrow<string>(undefined)
// getOrDefault
const defaulted: string = Maybe.getOrDefault<string>(undefined, 'default')
// getOrElse
const alternative: number = Maybe.getOrElse<number>(undefined, () => Date.now())
// isDefined
if (Maybe.isDefined(undefined)) {
// ...
}
// notDefined
if (Maybe.notDefined(undefined)) {
// ...
}