Hacker News Voting JavaScript

hacker-news.js

function byId(id) {
    return document.getElementById(id);
}

function vote(node) {
    var v = node.id.split(/_/); // {'up', '123'}
    var item = v[1];

    // hide arrows
    byId('up_' + item).style.visibility = 'hidden';
    byId('down_' + item).style.visibility = 'hidden';

    // ping server
    var ping = new Image();
    ping.src = node.href;

    return false; // cancel browser nav
}