parse_query.js

// "the pattern will be applied at most n - 1 times,
//  the array's length will be no greater than n,
//  and the array's last entry will contain all input
//  beyond the last matched delimiter"
// java_split("a=b=c", "=", 2) => ["a", "b=c"]
function java_split(s, sep, max_num_elements) {
    // "stops when limit entries have been placed into the array"
    // "a=b=c".split("=", 2) => ["a", "b"]
    var p = s.split(sep, max_num_elements);
    var stopped_length = p.reduce((acc, v) => acc + v.length + sep.length, 0);
    if (stopped_length <= s.length) {
        p[p.length - 1] += (sep + s.substring(stopped_length));
    }
    return p;
}

// Usage: 
// var params = parse_query(window.location.hash.substring(1));
// var value = params["key"];
function parse_query(q) {
    // BrunoLM https://stackoverflow.com/questions/901115/how-can-i-get-query-string-values-in-javascript
    if (q == "") return {};
    var qa = q.split('&');
    var params = {};
    for (var i = 0; i < qa.length; ++i) {
        var p = java_split(qa[i], '=', 2);
        var name = p[0];
        var value;
        if (p.length == 1) {
            value = "";
        } else {
            value = decodeURIComponent(p[1].replace(/\+/g, " "));
        }
        params[name] = value;
    }
    return params;
}