Currently, when attempting to accessing a nonexistent or non-exported object bar in a module object foo, the resulting error message is

Error in get(as.character(substitute(e2)), envir = e1, inherits = FALSE) :
   object 'bar' not found

This error message does not make it clear where the error is coming from. It needs to be improved. Something like this:

Error in foo$bar :
  no object 'bar' exported from module 'foo'