Thank you for your workarounds, Mark Bourne. `metavar` argument should be sufficient for infrequent use scenarios, and I will consider to use the custom help formatter if necessary.
>>> That's a bit closer to what you asked for, since the required argument >>> shown in the error message doesn't include the angle brackets. It also >>> avoids needing to specify a `metavar` for every positional argument. >>> However, it is overriding a non-public method of the `HelpFormatter` >>> class, so might not work across all Python versions if the name or >>> signature of that method changes (even if it does work with all current >>> versions, it might break in future). Your are right to be concerned, that’s why I still think, might the `argparse` can provide a more stable way which can set such format strategy globally, your workarounds are fine to work now, just I have to write the same code to parse either `metaver` or `formatter` every times I use argparse. Might can have different argparse subclasses, or make some HelpFormatter builtin, so that users won’t need to write them by themselves. -- https://mail.python.org/mailman/listinfo/python-list
