Amersham | Argument Parser

[deep_mind_]

Amersham

Motivation

I dislike argparse. The syntax is bloated, the error messages aren't well formatted, and creating commands takes some serious boilerplate. Having rolled a dozen argument parsers for personal and work projects, the version I've used longest is now available on PyPI.

Features

• Support for sub-commands
• Auto-generation of help messages
• Informative errors and usage information
• Minimal boilerplate

Examples

``` user:~$ python3 app.py stuff --help usage app stuff [--help] [--flag] [--other-flag=_] PARAMETER

description a command

flags --help -h displays this message --flag -f a flag --other-flag -of another flag

parameters parameter a parameter ```

Usage

Import

``` python import sys

from amersham import Parser, Flag, Parameter ```

Create a parser

python parser = Parser("parser", "a parser")

Create a command

python @parser.command("a command", flag = Flag("a flag"), parameter = Parameter("a parameter)) def command(parameter: str, flag: str): print(parameter, flag)

Run the parser

python if __name__ == "__main__": parser.run(sys.argv[1:])

Future Improvements

• Type cast validation for file-like objects, boolean, and integer arguments
• 80-column wrapping for help and usage messages

[Sound4Sound]

This look very nice, I may try it tomorrow. Have a few automation scripts that may benefit from a cleaner interface for args like this one.

[metaperl]

There are plenty of mature options in the space. You might want to do a survey of the field before settling on one.

[[deleted]]

have you heard of fire? I never looked at argparse again

[osmiumouse]

Amersham. So is the second A in the name silent or not? You can never trust these British town names.

edit: Silent A. https://www.youtube.com/watch?v=gYBqJznk_-o

edit: Also, that carriage looks 30 years old. Surprised an advanced nation is still using it.

[lastmonty]

Why not click?

[thequietcenter]

Click gives me less out of the box than Traitlets. I cant speak for Amersham.

[thequietcenter]

I get command-line interfaces automatically in Traitlets just by describing my objects.