in packages/sdk/src/FlagResolverClient.ts [362:374]
function resolvablePromise<T = void>(): [
promise: Promise<T>,
resolve: (value: T) => void,
reject: (reason: any) => void,
] {
let resolve: (value: T) => void;
let reject: (reason: any) => void;
const promise = new Promise<T>((_resolve, _reject) => {
resolve = _resolve;
reject = _reject;
});
return [promise, resolve!, reject!];
}