Lightweight argument parsing using a decorator


Keywords
argument-parser, command-line-parser, option-parser, python
Install
pip install parsable==0.2.3

Documentation

Parsable

Build status PyPI Version Anaconda Cloud Version

Parsable is a lightweight decorator-based command line parser library. Parsable was written to be simpler than argparse, optparse, and argh.

Installation

Install from PyPI with pip

pip install parsable

Or just download parsable.py and add to your project.

Usage

Parsable uses just two pieces of syntax: a @parsable command decorator, and a parsable() dispatch function.

  1. Import parsable.

    from parsable import parsable
  2. Decorate functions you want parsed. Parsable inspects the function to decide how to parse arguments. Arguments without default values are parsed as strings. Default arguments of any type T can be parsed as long as T(some_string) can do the parsing.

    @parsable
    def my_function(required_arg, optional_bool=True, optional_int=1):
        '''Help messages are not just a good idea, they are required'''
        # parsable automatically converts types based on default arguments:
        assert isinstance(required_arg, str)
        assert isinstance(optional_string, bool)
        assert isinstance(optional_int, int)
        # ...
    
    @parsable
    def do_stuff_with_files(*filenames, inplace=True):
        '''This does something to each file'''
        # ...
  3. Dispatch at the end of the script.

    if __name__ == '__main__':
        parsable()
  4. Use your new script

    $ python my_script.py my_function demo optional_int=5
    ...
    
    # parsable replaces - with _ to make functions easier to read
    $ python my_script.py do-stuff-with-files *.py inplace=false
    ...

Advanced Usage

To show verbose information (commmand name and timing info), set the environment variable PARSABLE_VERBOSE=true.

If you use parsable for many modules in a package, you can collect them in your setup.py using parsable.find_entry_points().

from parsable import parsable
from setuptools import setup

setup(
    name='my_package',
    entry_points=parsable.find_entry_points('my_package'),
    ...
)

LICENSE

Parsable is dual-licensed under the MIT and GPL2 licenses.