不要在最后一个位置参数之后解析选项 [英] Don't parse options after the last positional argument

问题描述

我正在围绕ssh命令行客户端编写包装器.在command的第一个位置参数之后，所有其他选项也应视为位置参数.

I'm writing a wrapper around the ssh command line client. After the first positional argument that's part of command, all further options should also be treated as positional arguments.

在optparse下，我相信可以使用 disable_interspersed_args .

Under optparse, I believe this would be done with disable_interspersed_args.

目前我有这样的东西:

parser = argparse.ArgumentParser()
parser.add_argument('--parallel', default=False, action='store_true')
# maybe allow no command? this would ssh interactively into each machine...
parser.add_argument('command', nargs='+')
args = parser.parse_args()

但是，如果选项作为命令的一部分传递(例如my_wrapper ls -l)，则它们会被ArgumentParser解释为未知选项. error: unrecognized arguments: -l

But if options are passed as part of the command (such as my_wrapper ls -l), they're instead interpreted by ArgumentParser as unknown options. error: unrecognized arguments: -l

如果我使用 parse_known_args() ，则这些选项可能会被删除的顺序.

If I use parse_known_args(), the options may be taken out of order.

p = argparse.ArgumentParser()
p.add_argument('-a', action='store_true')
p.add_argument('command', nargs='+')
print(p.parse_known_args())

$ python3 bah.py -b ls -l -a
(Namespace(a=True, command=['ls']), ['-b', '-l'])

在这里您可以看到ls之前的-b位置已经丢失，并且已经从命令中解析了-a，这是不希望的.

Here you can see that -b's position before ls has been lost, and -a has been parsed out from the command, which is not desired.

我如何:

• 防止参数在特定时间点后被解析?
• 是否禁用对散布参数的解析?
• 是否允许将带有前缀的参数用作位置参数?

推荐答案

我遇到了同样的问题.我在argparse错误跟踪器上找到了解决方案: http://code.google .com/p/argparse/issues/detail?id = 52

I had the same problem. I found the solution on the argparse bug tracker: http://code.google.com/p/argparse/issues/detail?id=52

解决方案很简单:将nargs='+'(或'*')替换为nargs=argparse.REMAINDER.此特殊值未记录，但可以满足您的要求.

The solution is simple: replace nargs='+' (or '*') with nargs=argparse.REMAINDER. This special value is not documented, but it does what you want.

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