code: func (m *Meta) initConfigLoader() (*configload.Loader, error) {
  	if m.configLoader == nil {
  		loader, err := configload.NewLoader(&configload.Config{
  			ModulesDir: m.modulesDir(),
  			Services:   m.Services,
  		})
  		if err != nil {
  			return nil, err
  		}
  		m.configLoader = loader
  	}
  	return m.configLoader, nil
  }
docs: // initConfigLoader initializes the shared configuration loader if it isn't
  // already initialized.
  //
  // If the loader cannot be created for some reason then an error is returned
  // and no loader is created. Subsequent calls will presumably see the same
  // error. Loader initialization errors will tend to prevent any further use
  // of most Terraform features, so callers should report any error and safely
  // terminate.