private void permuteSubroutineInInterfaceBlocks() {
    for (Definition declaration : getInterfaceDeclarations()) {
      ASTSubroutineStmtNode subroutineStmt =
          declaration.getTokenRef().findToken().findNearestAncestor(ASTSubroutineStmtNode.class);

      if (subroutineStmt != null
          && subroutineStmt.getSubroutinePars() != null
          && subroutineStmt.getSubroutinePars().size() == newParameterList.size())
        permuteDummyArguments(subroutineStmt);
    }
  }
  public List<ASTSubroutineParNode> getSubroutineParameters() {
    if (selectedSubroutine.getSubroutinePars() != null)
      return selectedSubroutine.getSubroutinePars();

    return new ArrayList<ASTSubroutineParNode>();
  }