@quantlab/handsontable/demo/bower_components/moment/src/lib/utils/extend.js

Spreadsheet-like data grid editor that provides copy/paste functionality compatible with Excel/Google Docs

import hasOwnProp from './has-own-prop';

export default function extend(a, b) {
    for (var i in b) {
        if (hasOwnProp(b, i)) {
            a[i] = b[i];
        }
    }

    if (hasOwnProp(b, 'toString')) {
        a.toString = b.toString;
    }

    if (hasOwnProp(b, 'valueOf')) {
        a.valueOf = b.valueOf;
    }

    return a;
}