docs: public void help() {
          p("");
          p("Command                Description");
          p("=======                ===========");
          p("help()                 Display usage and help messages. ");
          p("defineClass(className) Define an extension using the Java class");
          p("                       named with the string argument. ");
          p("                       Uses ScriptableObject.defineClass(). ");
          p("load(['foo.js', ...])  Load JavaScript source files named by ");
          p("                       string arguments. ");
          p("loadClass(className)   Load a class named by a string argument.");
          p("                       The class must be a script compiled to a");
          p("                       class file. ");
          p("print([expr ...])      Evaluate and print expressions. ");
          p("quit()                 Quit the shell. ");
          p("version([number])      Get or set the JavaScript version number.");
          p("");
      }