option-t
Version:
A toolkit of Nullable/Option/Result type implementation in ECMAScript. Their APIs are inspired by Rust's `Option<T>` and `Result<T, E>`.
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TypeScript
import type { EffectFn } from '../../../internal/function.js';
import type { Mutable } from '../../../internal/mutable.js';
import { type Option, type Some } from '../option.js';
export type MutSome<out T> = Mutable<Some<T>>;
export type UnsafeSomeDestructorFn<in T> = EffectFn<MutSome<T>>;
/**
* The _mutator_ is called if _input_ is `Some<T>`.
*
* This function allows you to cut the reference to the contain value from the inputted _input_.
* However, it would be unsafe operation if you do some more operation after this.
* For example, you can write the following code.
*
* ```javascript
* const some = createSome(1);
* unsafeDropForOption(some, (some) => {
* some.ok = false;
* });
* isSome(some); // -> false. This is dangerous.
* ```
*
* Compared to Rust, JavaScript does not have ownership semantics in language
* and this API is designed to use as a destructor or similar fashions.
* So if you call this for same object more than once, your code might contain "double free" problem.
*
* @throws
* This throw an `Error` instance if the _input_ is frozen.
*/
export declare function unsafeDropForOption<T>(input: Option<T>, mutator: UnsafeSomeDestructorFn<T>): void;