optional

Callable

• optional<T, O>(arbitrary: Arbitrary<T>, constraints?: MaybePartial<OptionalGenerator<O>>): Nothing extends O ? Dependent<Maybe<T>> : Dependent<O | T>

---

• optional takes an arbitrary and returns an arbitrary that is either the original arbitrary or the optional symbol

  Example

  random(optional(integer()))
  // => Nothing
  
  random(optional(integer()))
  // => 1234
  
  random(optional(integer({symbol: undefined})))
  // => undefined

  ---

  Type parameters

  • T
  • O = typeof Nothing

  Parameters

  • arbitrary: Arbitrary<T>

    The arbitrary to make optional.

  • constraints: MaybePartial<OptionalGenerator<O>> = {}

    The constraints used to generate arbitrary values.

  Returns Nothing extends O ? Dependent<Maybe<T>> : Dependent<O | T>

  An optional version of the given arbitrary.