list_known.js

var http = require('http'),
        registry = 'http://registry.npmjs.org/typescript/';

var list_known = function () {
        http.get(registry, function(res) {
                var data = '';
                res.setEncoding('utf8')
                res.on('data', function(str) {
                        data += str;
                }).on('end', function() {
                        var versions = Object.keys(JSON.parse(data).versions);
                        versions.forEach(function (versions) {
                                console.log('v' + versions);
                        });
                });
        });
};

var argv = process.argv;

if (argv[2] === 'list' && argv[3] === 'known') {
        list_known();
}