Flat ArgumentsΒΆ

Sometimes it’s more elegant to provide some arguments as flat, sequential values rather than by keyword. In this case, use the addflat() method:

def __init__(self, *args, **kwargs):
    self.options = Quoter.options.push(kwargs)
    self.options.addflat(args, ['prefix', 'suffix'])

to consume optional prefix and suffix flat arguments. This makes the following equivalent:

q1 = Quoter('[', ']')
q2 = Quoter(prefix='[', suffix=']')

An explicit addflat() method is provided not as much for Zen of Python reasons (“Explicit is better than implicit.”), but because flat arguments are commonly combined with abbreviation/shorthand conventions, which may require some logic to implement. For example, if only a prefix is given as a flat argument, you may want to use the same value to implicitly set the suffix. To this end, addflat returns the set of keys that it consumed:

if args:
    used = self.options.addflat(args, ['prefix', 'suffix'])
    if 'suffix' not in used:
        self.options.suffix = self.options.prefix