Function getOrCreateLoad

src/system-core.js:80–210

(loader, id, firstParentUrl, meta)

};

export function getOrCreateLoad (loader, id, firstParentUrl, meta) {
  var load = loader[REGISTRY][id];
  if (load)
    return load;

  var importerSetters = [];
  var ns = Object.create(null);
  if (toStringTag)
    Object.defineProperty(ns, toStringTag, { value: 'Module' });

  var instantiatePromise = Promise.resolve()
  .then(function () {
    return loader.instantiate(id, firstParentUrl, meta);
  })
  .then(function (registration) {
    if (!registration)
      throw Error(errMsg(2, process.env.SYSTEM_PRODUCTION ? id : 'Module ' + id + ' did not instantiate'));
    function _export (name, value) {
      // note if we have hoisted exports (including reexports)
      load.h = true;
      var changed = false;
      if (typeof name === 'string') {
        if (!(name in ns) || ns[name] !== value) {
          ns[name] = value;
          changed = true;
        }
      }
      else {
        for (var p in name) {
          var value = name[p];
          if (!(p in ns) || ns[p] !== value) {
            ns[p] = value;
            changed = true;
          }
        }

        if (name && name.__esModule) {
          ns.__esModule = name.__esModule;
        }
      }
      if (changed)
        for (var i = 0; i < importerSetters.length; i++) {
          var setter = importerSetters[i];
          if (setter) setter(ns);
        }
      return value;
    }
    var declared = registration[1](_export, registration[1].length === 2 ? {
      import: function (importId, meta) {
        return loader.import(importId, id, meta);
      },
      meta: loader.createContext(id)
    } : undefined);
    load.e = declared.execute || function () {};
    return [registration[0], declared.setters || [], registration[2] || []];
  }, function (err) {
    load.e = null;
    load.er = err;