
Python Decorators are wrappers that you may apply around methods. So they're rather like the bread around a sandwich.
There are a number of standard decorators provided with Python - such as @classmethod and @staticmethod (see
[here]) which allow you to turn methods into unbound (static, class) ones. You can also set up your own decorator - there's and example of that
[here].
Here's how I can define my own decorator:
def summat(f):
"Definition of your own decorator"
def action(*args,**kwargs):
result = f(*args,**kwargs)
print "Err ... ",
return result
return action
How I wrap a method using it:
@summat
def getstuff(self):
return self.stuff
And an example of how I call it:
print them.getstuff()
When should you use decorators? There are lots of potential uses - the first "classic" demonstration is for logging calls to methods, but it could also be used to provide overall / management controls on actions - such as ensuring that databases are open, or keeping tables of details of widgets in a GUI.
Illustration © - public domain image
(written 2010-05-14)
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