Optional overview

Added in v1.0.0

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Table of contents

• Combinators
  • Optional

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Combinators

Optional

A schema that widens a schema to include undefined. Also marks the input property of a struct as optional.

Optional property fallbackInput is used to provide a default value for transcoders and json-schemas.

Signature

export declare const Optional: <I, O, Fallback extends I | undefined = undefined>(
  target: Schema<I, O>,
  fallbackInput?: Fallback | undefined
) => Fallback extends undefined
  ? ImplicitOptional & Schema<I | undefined, O | undefined>
  : ImplicitOptional & Schema<I | undefined, O>

Added in v1.0.0