Comment originally made by @loganfsmyth

Hmm, tough one. In the short-term you'd have to do import {event} from 'd3';

Seems to me like the most correct approach here would be for _interopRequireWildcard to return an object with getter properties instead, but that'd potentially be a performance hit. Another alternative would be

var newObj = Object.create(obj);
newObj.default = obj;

but that'd be non-spec since the properties wouldn't be own properties.

Comment originally made by @abergenw

In d3 event is not exported separately so I cannot do import {event} from 'd3'. However I solved this by forking d3 and providing a getter.

I can't say what the most correct solution would be, but since it's not very common to expose mutable fields like this, perhaps a solution would be to simply turn off interop for certain modules by configuring transform-es2015-modules-commonjs with the necessary parameters.

Comment originally made by @loganfsmyth

@abergenw import {event} from 'd3'; console.log(event) is essentially the same as import * as d3 from 'd3'; console.log(d3.event); Since d3 is CommonJS, you should also be able to do import d3 from 'd3'; console.log(d3.event);.

Only import * as d3 from 'd3' will incorrectly handle the live behavior of event, so you have several options.

Comment originally made by @abergenw

Yes correct, thank you. I can get around the problem by using any other means of importing than the namespace/wildcard syntax (my typescript definitions fooled me I couldn't). I still think however that the way _interopRequireWildcard works may cause more harm than good. Cheers!

Would reimplementing the _interopRequireWildcard helper like this work? It doesn't clone the imported namespace, but it creates a new object and sets __proto__ to the module.exports of the imported module.

function _interopRequireWildcard(obj) {
  if (obj && obj.__esModule) {
    return obj;
  } else {
    function C() { this.default = obj; }
    C.prototype = obj;
    return new C;
  }
}

Current implementation:

function _interopRequireWildcard(obj) {
  if (obj && obj.__esModule) {
    return obj;
  } else {
    var newObj = {};
    if (obj != null) {
      for (var key in obj) {
        if (Object.prototype.hasOwnProperty.call(obj, key)) {
          var desc =
            Object.defineProperty && Object.getOwnPropertyDescriptor
              ? Object.getOwnPropertyDescriptor(obj, key)
              : {};
          if (desc.get || desc.set) {
            Object.defineProperty(newObj, key, desc);
          } else {
            newObj[key] = obj[key];
          }
        }
      }
    }
    newObj.default = obj;
    return newObj;
  }
}