On Thu, 06 Oct 2005 07:15:12 -0700, Robert Kern <[EMAIL PROTECTED]> wrote:
>Flavio wrote:
>> Ok, its not thousands, but more like dozens of variables...
>> I am reading a large form from the web which returns a lot of values.
>> (I am Using cherrypy)
>>
>> I know I could pass these variables around as:
>>
>> def some_function(**variables):
>> ...
>>
>> some_function(**variables)
>>
>> but its a pain in the neck to have to refer to them as
>> variables['whatever']...
>>
>> dont you think?
>
>Use a Bunch.
>
>class Bunch(dict):
> def __init__(self, *args, **kwds):
> dict.__init__(self, *args, **kwds)
> self.__dict__ = self
>
>--
Or use a version-sensitive byte-code hack to set some preset locals before
executing,
either with one-time presets via normal decorator, e.g.,
>>> from ut.presets import presets
>>> @presets(x=111, y=222, z='zee')
... def foo():
... return locals()
...
>>> foo()
{'y': 222, 'x': 111, 'z': 'zee'}
Or the same, just using a predefined dict instead of the keyword format:
>>> e = {'a':0, 'b':1}
>>> @presets(**e)
... def foo():
... return locals()
...
>>> foo()
{'a': 0, 'b': 1}
What happened to foo viat the decoration:
>>> import dis
>>> dis.dis(foo)
1 0 LOAD_CONST 1 ((0, 1))
3 UNPACK_SEQUENCE 2
6 STORE_FAST 0 (a)
9 STORE_FAST 1 (b)
3 12 LOAD_GLOBAL 0 (locals)
15 CALL_FUNCTION 0
18 RETURN_VALUE
To mess with the same base function with different presets more dynamically,
use the explicit way of calling the decorator:
The base function:
>>> def bar(x, y=123):
... return locals()
...
decorate and invoke on the fly with particular presets:
>>> presets(**e)(bar)('exx')
{'a': 0, 'y': 123, 'b': 1, 'x': 'exx'}
The keyword way:
>>> presets(hey='there')(bar)('exx')
{'y': 123, 'x': 'exx', 'hey': 'there'}
BTW, @presets does not change the signature of the function whose selected
locals
are being preset from the decoration-time-generated constant, e.g.,
>>> presets(hey='there')(bar)()
Traceback (most recent call last):
File "<stdin>", line 1, in ?
TypeError: bar() takes at least 1 argument (0 given)
>>> presets(hey='there')(bar)('exx', 'wye')
{'y': 'wye', 'x': 'exx', 'hey': 'there'}
>>> presets(hey='there')(bar)('exx', 'wye', 'zee')
Traceback (most recent call last):
File "<stdin>", line 1, in ?
TypeError: bar() takes at most 2 arguments (3 given)
Regards,
Bengt Richter
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