Python vs. Perl

[Alex Martelli]

"Thomas Wouters" <thomas at xs4all.net> wrote in message
news:mailman.990779859.18387.python-list at python.org...
    ...
> if you want to keep statistics on how your functions are used, you don't
> have to change all your functions. You simply create a wrapper-class
around
> all your functions, that logs how and from where they are used, and then
> calls the original function. (Python classes can be callable, too.)

Yes, but what they do when you do call them is create an instance
object belonging to said class -- not very usable as a wrapper for
general-purpose functions.  I suspect you mean to refer to the
fact that *instances* can be callable (and an instance *CAN* most
easily do the task you mention) rather than to that, equally true
but seemingly not very relevant in context, that classes are.

Wrapping all callables in (e.g.) a module so the wrappers count
how many times they're called is a suitable exercise for a Python
beginning to intermediate student -- the kind of thing somebody
already highly experienced in other languages will do like crazy
when he's been Pythoning for a month or so, because it's so easy
and fun it really goes to your head (unless your background is
in Lisp or thereabouts, I guess, since then the tricks may be old
hat to you... but even then, it may be fun to see how the approach
works without macros, without s-lists, etc, and still quite well).


> meant general-purpose/performance, not just 'more features'. You can stuff
> any hashable Python object in a Python hash, both as key and as value, and

True, but the value (as opposed to the key) doesn't even need to
be hashable, does it?


Alex