Variable ifDefined`Const`

ifDefined: <T>(value: T) => typeof nothing | NonNullable<T>

For AttributeParts, sets the attribute if the value is defined and removes the attribute if the value is undefined.

For other part types, this directive is a no-op.

Type declaration

- <T>(value: T): typeof nothing | NonNullable<T>
- Type Parameters
  - T
  Parameters
  - value: T
  Returns typeof nothing | NonNullable<T>