ARGV.py

"""
Allows one to handle *args and **kwargs together in an intuitive way:

api.create_thing('my-thing', 'property-1', 'property-2')

or
api.create_thing('my-thing', prop2='property-2')

or
api.create_thing(**config)

>>> def myfunc(*args, **kwargs):
...     argv = ARGV(args, kwargs)
...     return argv.get(0, 'foo', 'FOO')
...
>>> myfunc('bar')
'bar'
>>> myfunc(foo='baz')
'baz'
>>> myfunc(bar='baz')
'FOO'
>>> myfunc()
'FOO'
"""
class ARGV:
    def __init__(self, args, kwargs):
        self.args = args
        self.kwargs = kwargs
        self.argc = len(args) + len(kwargs)

    def arg(self, idx, default=None):
        try:
            return self.args[idx]
        except IndexError:
            return default

    def kwarg(self, key, default=None):
        try:
            return self.kwargs[key]
        except KeyError:
            return default

    def get(self, idx, key=None, default=None):
        """
        Looks for an arg at an index, or a fallback kwarg.
        Returns `default` if neither is found
        """
        try:
            return self.args[idx]
        except IndexError:
            try:
                return self.kwargs[key]
            except KeyError:
                return default