gistfile1.txt

var modules = {};
var _require;
var require = _require = function(scriptName) {
  if (modules[scriptName] === undefined) {
    console.error("require('" + scriptName + "'): file not found.");
    return;
  }
  if (modules[scriptName].cached) {
    return modules[scriptName].cached;
  }
  else {
    return modules[scriptName]();
  }
}

function module(scriptName, scriptContent) {
  modules[scriptName] = function() {
    var exports = {};
    var require = function (scriptName) {
      return _require(scriptName);
    };
    modules[scriptName].cached = exports;
    (function() {
      scriptContent(exports);
    }).call(exports);
    return exports;
  }
}