.js

function getFoos(nextOffset, results) {
    nextOffset = nextOffset || 0;
    results = results || [ ];
    
    return Promise.try(() => {
        return getSomeFoos(nextOffset);
    }).then(res => {
        let newResults = results.concat(res.foos);
        return res.hasMore ?
            getFoos(res.nextOffset, newResults) :
            newResults
    });
}