# EmptyInput

> This document is the Markdown version of [formisch.dev/core/api/EmptyInput/](https://formisch.dev/core/api/EmptyInput/). For the complete documentation index, see [llms.txt](https://formisch.dev/llms.txt).

Empty input interface that defines the value a required field of a given type starts at when no initial input is provided. Optional and nullable fields are not affected, as they accept `undefined`.

## Definition

- `EmptyInput`
  - `string` `string | undefined`
  - `number` `number | undefined`
  - `boolean` `boolean | undefined`
  - `date` `Date | undefined`

### Explanation

Only required fields whose input is `undefined` fall back to these values. The `string` property defaults to an empty string so that an untouched field matches the DOM and validates with its own message instead of a type mismatch. The other properties default to `undefined`.

## Related

### Primitives

[`useForm`](/react/api/useForm.md)

### Types

[`FormConfig`](/react/api/FormConfig.md)