URI implementation

example.js

var uri_builder = require('./uri.js');
var service_uri = uri_builder('http://api.example.com');
var collection_uri = service_uri('/users');
console.log(require('url').format(collection_uri));

uri.js

/** Returns an URI parser as a function.
 * @param value string|object|function URI to parse 
 * @returns New function([value]) which returns the URI parsed into an 
 * object. You can change the returned object by providing changes in 
 * an optional value argument. Value can be string, object or 
 * URI parser as a function.
 */
function uri_builder(value) {
    var uri;
    function do_parse(v) {
        if(v && (typeof v === 'function')) {
            return v();
        } else {
            return (v && (typeof v === 'object')) ? v : require('url').parse(v);
        }
    }
    uri = function do_uri(value2) {
        if(value2 === undefined) return do_parse(value);
        var opts = do_parse(value), opts2 = do_parse(value2);
        Object.keys(opts2).map(function(key) {
            opts[key] = opts2[key];
        });
        return opts;
    };
    return uri;
}

module.exports = uri_builder;