docs: public static Expect4j expStateCurrent(Interp interp) throws TclException {
          TclObject spawnObj = interp.getVar("spawn_id", 0); // confirm that this works and we don't need TCL.NAMESPACE_ONLY
  
          Map spawnIds = (Map) interp.getAssocData("spawnIds");
          if( spawnIds == null )
              throw new TclException(interp, "spawn not called yet");
  
          String spawnId = spawnObj.toString();
          if( !spawnIds.containsKey(spawnId) )
              throw new TclException(interp, "Unable to find spawn_id of " + spawnId);
  
          Expect4j expect4j = (Expect4j) spawnIds.get(spawnId);
          if( expect4j == null )
              throw new TclException(interp, "Unable to find Expect context from " + spawnId);
  
          return expect4j;
      }