python - tornado中使用parse_command_line(final=False) 沒能理解final是做什么的
問題描述
大概知道parse_command_line是用來解析命令行的,但是不理解里面的final參數(shù)是作什么的。順便咨詢一下學(xué)習(xí)tonardo的學(xué)習(xí)資源(知道官方文檔是最好的)和書籍
問題解答
回答1:通過這樣,找到源代碼,請自己看方法文檔
If final is False, parse callbacks will not be run.
This is useful for applications that wish to combine configurationsfrom multiple sources.
def parse_command_line(self, args=None, final=True):'''Parses all options given on the command line (defaults to`sys.argv`).Note that ``args[0]`` is ignored since it is the program namein `sys.argv`.We return a list of all arguments that are not parsed as options.If ``final`` is ``False``, parse callbacks will not be run.This is useful for applications that wish to combine configurationsfrom multiple sources.'''if args is None: args = sys.argvremaining = []for i in range(1, len(args)): # All things after the last option are command line arguments if not args[i].startswith('-'):remaining = args[i:]break if args[i] == '--':remaining = args[i + 1:]break arg = args[i].lstrip('-') name, equals, value = arg.partition('=') name = self._normalize_name(name) if name not in self._options:self.print_help()raise Error(’Unrecognized command line option: %r’ % name) option = self._options[name] if not equals:if option.type == bool: value = 'true'else: raise Error(’Option %r requires a value’ % name) option.parse(value)if final: self.run_parse_callbacks()return remaining
相關(guān)文章:
1. docker-machine添加一個已有的docker主機(jī)問題2. javascript - 關(guān)于圣杯布局的一點(diǎn)疑惑3. 關(guān)于docker下的nginx壓力測試4. php - mysql 模糊搜索問題5. mysql - 在下剛?cè)腴Tsql 關(guān)于sql的語法詢問6. 數(shù)組 - mysql 輸出到 php array 然後印出?7. 我和老師的代碼對照了幾遍沒發(fā)現(xiàn)問題,但是瀏覽器打開就有問題了,求解8. MySQL視圖count速度優(yōu)化9. php新手疑問 利用自定義函數(shù)進(jìn)行加減乘除10. 異步 - python一些內(nèi)置的函數(shù)是阻塞還是非阻塞?
