code: public Object source( String filename, NameSpace nameSpace )
          throws FileNotFoundException, IOException, EvalError
      {
          File file = pathToFile( filename );
          Interpreter.debug("Sourcing file: ", file);
          Reader sourceIn = new BufferedReader( new FileReader(file) );
          try {
              return eval( sourceIn, nameSpace, filename );
          } finally {
              sourceIn.close();
          }
      }
docs: Read text from fileName and eval it.