docs: public final DRL5Expressions.operator_key_return operator_key() throws RecognitionException {
  		DRL5Expressions.operator_key_return retval = new DRL5Expressions.operator_key_return();
  		retval.start = input.LT(1);
  
  		Token id=null;
  
  		try {
  			// src/main/resources/org/drools/compiler/lang/DRL5Expressions.g:771:3: ({...}? =>id= ID )
  			// src/main/resources/org/drools/compiler/lang/DRL5Expressions.g:771:10: {...}? =>id= ID
  			{
  			if ( !(((helper.isPluggableEvaluator(false)))) ) {
  				if (state.backtracking>0) {state.failed=true; return retval;}
  				throw new FailedPredicateException(input, "operator_key", "(helper.isPluggableEvaluator(false))");
  			}
  			id=(Token)match(input,ID,FOLLOW_ID_in_operator_key4794); if (state.failed) return retval;
  			if ( state.backtracking==0 ) { helper.emit(id, DroolsEditorType.KEYWORD); }
  			}
  
  			retval.stop = input.LT(-1);
  
  		}
  
  		catch (RecognitionException re) {
  		    throw re;
  		}
  
  		finally {
  			// do for sure before leaving
  		}
  		return retval;
  	}