Class ZodNullable

packages/zod/src/v3/types.ts:4525–4549

export type ZodNullableType<T extends ZodTypeAny> = ZodNullable<T>;

export class ZodNullable<T extends ZodTypeAny> extends ZodType<
  T["_output"] | null,
  ZodNullableDef<T>,
  T["_input"] | null
> {
  _parse(input: ParseInput): ParseReturnType<this["_output"]> {
    const parsedType = this._getType(input);
    if (parsedType === ZodParsedType.null) {
      return OK(null);
    }
    return this._def.innerType._parse(input);
  }

  unwrap() {
    return this._def.innerType;
  }

  static create = <Inner extends ZodTypeAny>(type: Inner, params?: RawCreateParams): ZodNullable<Inner> => {
    return new ZodNullable({
      innerType: type,
      typeName: ZodFirstPartyTypeKind.ZodNullable,
      ...processCreateParams(params),
    }) as any;
  };
}

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