reverse_argparse

The reverse_argparse module provides a means of undoing the argument parsing provided by argparse. That is, it can take a argparse.Namespace of parsed command line arguments, along with the argparse.ArgumentParser that generated it, and then unparse everything into the exact list of command line arguments that was used when executing the script.

“But wait, if I just ran a script on the command line, I can see what I just typed in. Why would the script need to figure that out again so it could tell me something I can see right in front of me?”

Because reverse_argparse will take into consideration any default values, along with any transformations that have been made after argument parsing (e.g., path resolution, etc.). For more details on why this matters, check out the Motivation page.

Installation

To get up and running with reverse_argparse, simply

python3 -m pip install reverse-argparse

Usage

Once the package is installed, you can simply

from argparse import ArgumentParser

from reverse_argparse import ReverseArgumentParser

# Parse the command line arguments.
parser = ArgumentParser()
# Build out the parser however you like.
args = parser.parse_args()
# Optionally post-process any arguments, as needed.

# Do whatever you need to in the script.

# Wrap things up.
print("This script executed the following:")
unparser = ReverseArgumentParser(parser, args)
print(unparser.get_pretty_command_line_invocation())

For more detailed usage information, see the Examples page. For implementation details, see the reference documentation.

Contributing

The source repository for this module is on GitHub. See the project’s README and contributing guidelines for details on how to interact with the project.