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/** * Wraps a Promise and lets you observe its state. */export class StatefulPromise<T> implements Promise<T>{
    #state: PromiseState = "pending"    #inner: Promise<T>
    constructor(p: Promise<T>) {        this.#inner = p
        this.#watch(p)    }
    get state(): PromiseState { return this.#state }
    async #watch(p: Promise<T>) {        try {            await p            this.#state = "resolved"        } catch (_err) {            this.#state = "rejected"        }    }        // Wrappers. (Thanks, VSCode, for generating these types. :p)    then<TResult1=T,TResult2=never>(        onfulfilled?: ((value: T) => TResult1|PromiseLike<TResult1>)|null|undefined,        onrejected?: ((reason: unknown) => TResult2|PromiseLike<TResult2>)|null|undefined    ): Promise<TResult1|TResult2> {        return this.#inner.then(onfulfilled, onrejected)    }    catch<TResult=never>(        onrejected?: ((reason: unknown) => TResult|PromiseLike<TResult>)|null|undefined    ): Promise<T|TResult> {        return this.#inner.catch(onrejected)    }    finally(onfinally?: (() => void)|null|undefined): Promise<T> {        return this.#inner.finally(onfinally)    }
    [Symbol.toStringTag] = "StatefulPromise"
    }
export type PromiseState = "pending" | "resolved" | "rejected"
/** Shorter helper method */export function stateful<T>(p: Promise<T>): StatefulPromise<T> {    return new StatefulPromise(p)}