falcor-router/src/operations/ranges/normalize.js

A router DataSource constructor for falcor that allows you to model all your cloud data sources as a single JSON resource.

/**
 * takes in a range and normalizes it to have a to / from
 */
module.exports = function normalize(range) {
    var from = range.from || 0;
    var to;
    if (typeof range.to === 'number') {
        to = range.to;
    } else {
        to = from + range.length - 1;
    }

    return {to: to, from: from};
};