function compare(current, latest) {
var a = current.split(/./);
var b = latest.split(/./);
var len = a.length - b.length;
var type = 1;
if (len > 0) {
type = 2;
} else if (len < 0) {
type = 1;
}
len = Math.abs(len);
for (var i = 0; i < len; i++) {
type == 1 ? a.push('0') : b.push('0');
}
for (var k = 0; k < a.length; k++) {
var d = a[k].charCodeAt(0), c = b[k].charCodeAt(0)
if (d == c) {
continue
}
return c > d;
}
return false
}
var current = '2.2.a';
var latest = '2.2.b';
console.log(compare(current, latest))
