Python中exit、return、sys.exit()等使用实例和区别
有这样一道题目： 字符串标识符.修改例6-1的idcheck.py脚本,使之可以检测长度为一的标识符,并且可以识别Python关键字,对后一个要求,你可以使用keyword模块(特别是keyword.kelist)来帮你.
我最初的代码是：
#!/usr/bin/envpython
importstring importkeyword importsys
#Getallkeywordforpython #keyword.kwlist #['and','as','assert','break',...] keyWords=keyword.kwlist
#Getallcharacterforidentifier #string.letters==>'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz' #string.digits ==>'0123456789' charForId=string.letters+"_" numForId=string.digits
idInput=raw_input("Inputyourwords,please!")
ifidInputinkeyWords: print"%siskeywordfotPython!"%idInput else: lenNum=len(idInput) if(1==lenNum): if(idInputincharForIdandidInput!="_"): print"%sislegalidentifierforPython!"%idInput else: #It'sjust"_" print"%sisn'tlegalidentifierforPython!"%idInput
else: if(idInput[0:1]incharForId): legalstring=charForId+numForId foriteminidInput[1:]: if(itemnotinlegalstring): print"%sisn'tlegalidentifierforPython!"%idInput sys.exit(0) print"%sislegalidentifierforPython!2"%idInput else: print"%sisn'tlegalidentifierforPython!3"%idInput