Function arguments

[Laura Creighton]

> Call me weird, but sometimes I need functions taking a number of
> positional arguments, some named arguments with default values, and
> other named arguments as well.

<snip>

> I was thinking of a popitem() dictionary method taking
> (optionally) 2 arguments: the name of the item to pop,
> and the default value to return if the item is not present
> in the dictionary:
> 
> >>> d = {'a': 2, 'b': 3}
> >>> d.popitem('defarg', 0)
> 0
> >>> d
> {'a': 2, 'b': 3}
> >>> d.popitem('a', 100)
> 2
> >>> d
> {'b': 3}
> >>>
> 
> Opinions?

I do this frequently.  (Code yanked from what I happen to be working on
today).

class Field(Tkinter.Label):
    def __init__(self, parent, **kw):
        # these are the defaults that you will get if you haven't specified
        defaults={'borderwidth': 1,
                  'relief' : 'groove',
                  'width' : 30,
                  'height' : 2,
                  'anchor' : 'w',
                  'text' : 'SPAM SPAM SPAM SPAM',
                  }

        # overwrite any of the defaults with the dictionary you passed
        defaults.update(kw)

        Tkinter.Label.__init__(self, parent, **defaults)

and so on and so forth

Laura Creighton