Jesper Noehr

Since Python 2.5, Python has had the ‘functools’ module for doing various higher order functions.

For example:

from functools import partial

def adder(first, second):
	return first + second

adder10 = partial(adder, 10)

print adder10(32) # -> 42

Partial evaluation, eh? That’s kinda cool.

On to ‘wraps’ which is the one I’ve found most practical use for. I like decorators, and I use them where applicable. What I don’t like about decorators is that when you get a backtrace, it’ll actually show up as *that* function, and not the function you decorated.

‘wraps’ to the rescue:

from functools import wraps

def some_decorator(f):
	def wrap(*args, **kwargs):
		return f(*args, **kwargs)
	return wraps(f)(wrap)

@some_decorator
def some_function():
	...

Now the function name, docstring, signature, etc. will be that of ‘f’, no longer ‘wrap’! Immensely useful.