>>> import inspect
>>> help(inspect.getargspec)
Help on function getargspec in module inspect:
getargspec(func)
Get the names and default values of a function's arguments.
A tuple of four things is returned: (args, varargs, varkw, defaults).
'args' is a list of the argument names (it may contain nested lists).
'varargs' and 'varkw' are the names of the * and ** arguments or None.
'defaults' is an n-tuple of the default values of the last n arguments.
What conditions would you guess might cause getargspec's args list to contain nested lists?
Monday, April 11, 2005
how well do you know python, part 3
Here's one to file in the "cryptic documentation" category.
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3 comments:
If the arg list contains a tuple:
>>> import inspect
>>> def a((b,c,d),e):
... pass
...
>>> inspect.getargspec(a)
([['b', 'c', 'd'], 'e'], None, None, None)
Why you'd want to refer to a function's arg's tuple elements directly, I'm not quite sure... maybe if you wanted to force a certain number of elements in the tuple.
Heck, I didn't even know you could do that.
That's pretty neat -- and begging for some abuse ;)
I find it mainly useful for documenting function structure:
def parse_email(email_tuple):
...
def parse_email((header, body)):
...
The main gain here is not so much in documenting how many elements an email_tuple has, but what order they come in - this is particularly useful if you're the kind of programmer (like I am) who throws around a lot of tuples.
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