Complex types are allowed in string elements

[GrizzIL]

This expression:

InstanceOf: Patient
* name
  * family =  {"Identifier": "yutityui","Text": "sfdgsdf"}

Should throw an error since it's a primitive element, but the transformation is done without errors and the object inserted into the string element:

{
  "resourceType": "Patient",
  "name": [
    {
      "family": {
        "Identifier": "yutityui",
        "Text": "sfdgsdf"
      }
    }
  ]
}