[Python-ideas] Access to function objects

David Townshend aquavitae69 at gmail.com
Sat Aug 6 10:10:06 CEST 2011

Has anyone else ever thought that it might be useful to access a function
object from within the call?  I've come across this situation a few times
recently, and thought it would be very useful to be able to do something
like, for example:

def a_function() as func:

It would be useful, for example, to record state between calls, or if the
function wants to reuse its own properties (like in the above example).
 Consider a function which should print the number of times it has been
called on every call

def counter(add) as func:
    if not hasattr(func, 'count'):
        func.count = 0
    func.count += 1

This could also be implemented using classes, i.e.

class Counter:
    def __call__(self, add):
        if not hasattr(func, 'count'):
            func.count = 0
        func.count += 1
counter = Counter()

But this is much more clumsy, results in an extra object (the Counter class)
and will be quite complicated if counter is a method rather than a function.

The reason I've used "as" syntax is that it is consistent with other python
statements (e.g. "with" and "except"), wouldn't require a new keyword and is
backwardly compatible.

Any thoughts?

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