Is $ a valid module name?

Hi @benjamn, we got this issue on Meteor https://github.com/meteor/meteor/issues/11279

I believe it is because X6 is using `import $` and then reify is breaking in this case.

Am I right? Is this a valid module name?

Start by reproducing the linked Meteor issue and examining the reported X6 `import $` case in reify. Confirm whether the syntax is valid and identify whether reify mishandles it; the issue is complete when the behavior is explained and any necessary handling is fixed or documented.

Written by the indexing model from the issue text.