async-find.js

const Promise = require('bluebird');

const findAsync = (predicate, items) => {
    if (items.length < 1) {
        return Promise.resolve(undefined);
    }

    const [current, ...rest] = items;

    return predicate(current)
        .then(match => {
            if (match) {
                return current;
            }

            return findAsync(predicate, rest);
        });
}

const slowPredicate = (actualPredicate, item) => {
    console.log("Starting slow predicate", item);
    return new Promise((resolve, reject) => {
        setTimeout(() => {
            resolve(actualPredicate(item));
        }, 200);
    })
}

findAsync((item) => slowPredicate(i => i === "me!", item), ["you", "can't", "find", "me!", "I'm", "hiding"])
    .then(found => {
        console.log("Found:", found);
    });