import type { Mutable } from '../../../internal/mutable.js';
import type { Option } from '../option.js';
/**
 *  This allows to mutate the value to save needless allocation.
 *
 *  We don't define `MutSome<T>` or `MutNone` because we can always mutable properties on `MutOption<T>`.
 *  This means that it's hard to check the type on static type system.
 */
export type MutOption<T> = Mutable<Option<T>>;
/**
 *  @throws
 *  This throw an `Error` instance if the _input_ is frozen.
 */
export declare function unsafeAsMutOption<T>(input: Option<T>): MutOption<T>;