Python argparse 切换标志 [英] Python argparse toggle flags

问题描述

argparse 有没有办法解析像 [+-]a,b,c,d 这样的标志?

Is there any way in argparse to parse flags like [+-]a,b,c,d?

foo.py +s -b

应该在s的dest中存储True，在b的dest中存储False，很像done通过 Windows attrib 或 Linux chmod.

should store True in the dest of s and False in the dest of b, much like done by the Windows attrib or the Linux chmod.

目前，我分别使用 +s 和 -s 和 store_true 和 store_false 两个单独的参数.但它创建了一个丑陋的帮助，它将每个标志列出两次(+a & -a)

Currently, I am using 2 separate arguments +s and -s with store_true and store_false, respectively. But it creates an ugly help with it listing each flag twice (+a & -a)

另一种解决方法是使用正则表达式手动解析扩展的 arg(不知何故似乎更容易并使用自定义描述，但是在此之前我只想环顾四周是否有任何使用 which我可以使用 argparse 本身执行相同的操作.

Another workaround would be to manually parse the extended arg with regex (which somehow seems a lot easier and use custom description, but before doing that I just wanted to look around if there was anything using which I could perform the same thing using argparse itself.

推荐答案

您可以通过将 -s 和 +s 传递给单个 add_argument 来实现 调用，并使用自定义操作:

You can do this by passing both -s and +s to a single add_argument call, and using a custom action:

class ToggleAction(argparse.Action):
    def __call__(self, parser, ns, values, option):
        setattr(ns, self.dest, bool("-+".index(option[0])))
ap = ArgumentParser(prefix_chars='-+')
ap.add_argument('-s', '+s', action=ToggleAction, nargs=0)

ap.parse_args(['+s'])
Namespace(s=True)

ap.parse_args(['-s'])
Namespace(s=False)

这篇关于Python argparse 切换标志的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！