如何将％d添加到argparse帮助文本(How to add %d to argparse help text)

如何将％d添加到argparse帮助文本(How to add %d to argparse help text)

我面临这个问题与python 2.6.1 argparse 0.8，我需要添加%d来帮助描述例如

import argparse parser = argparse.ArgumentParser() parser.add_argument('--range', metavar='range', type=str, help='generates a list of host from given range e.g. "host%d.example.com 1 224"') args = parser.parse_args()

它会抛出错误

$ ./args.py -h ... python2.6/site-packages/argparse.py", line 458, in _expand_help return action.help % params TypeError: %d format: a number is required, not dict

我可以理解，所以我试图逃避%例如

parser.add_argument('--range', metavar='range', type=str, help='generates a list of host from given range e.g. "host%%d.example.com 1 224"')

但我仍然遇到另一个错误

$ ./args.py -h ... python2.6/site-packages/argparse.py", line 252, in format_help help = self._root_section.format_help() % dict(prog=self._prog) TypeError: %d format: a number is required, not dict

所以我不确定如何正确转义% ，以便在帮助输出中看到%d

I am facing this problem with python 2.6.1 argparse 0.8 , I need to add %d to help description e.g.

import argparse parser = argparse.ArgumentParser() parser.add_argument('--range', metavar='range', type=str, help='generates a list of host from given range e.g. "host%d.example.com 1 224"') args = parser.parse_args()

It throws error

$ ./args.py -h ... python2.6/site-packages/argparse.py", line 458, in _expand_help return action.help % params TypeError: %d format: a number is required, not dict

Which I can understand, so I tried to escape % e.g.

parser.add_argument('--range', metavar='range', type=str, help='generates a list of host from given range e.g. "host%%d.example.com 1 224"')

But I still get another error

$ ./args.py -h ... python2.6/site-packages/argparse.py", line 252, in format_help help = self._root_section.format_help() % dict(prog=self._prog) TypeError: %d format: a number is required, not dict

So I am not sure how to escape % properly so that I can see %d in help output

最满意答案

由于argparse格式化字符串两次，出现2个错误，解决方案是双重转义% ：

parser.add_argument('--range', metavar='range', type=str, help='generates a list of host from given range e.g. "host%%%%d.example.com 1 224"')

这是4 % 。

Since argparse is formatting the string twice, giving 2 errors, the solution is to double-escape the %:

parser.add_argument('--range', metavar='range', type=str, help='generates a list of host from given range e.g. "host%%%%d.example.com 1 224"')

That's 4 %s.