1b8e80941Smrg#define empty 2b8e80941Smrg<empty< 3b8e80941Smrg<empty= 4b8e80941Smrg>empty> 5b8e80941Smrg>empty= 6b8e80941Smrg=empty= 7b8e80941Smrg!empty= 8b8e80941Smrg&empty& 9b8e80941Smrg|empty| 10b8e80941Smrg+empty+ 11b8e80941Smrg-empty- 12