Python documentation for @?

Question

Just a quick question,

Could someone link me to the documentation for the use of @ in python?

Due not being able to google @ and not knowing the use or name of it I'm not sure how to find it on my own :)

Many thanks!!

Very similar question to http://stackoverflow.com/questions/5337890/python-at-prefix-in-top-level-module-code-what-does-it-stand-for/5337982#5337982 — eat, Apr 01 '11 at 14:03

masterpiga · Accepted Answer · 2011-04-01T14:01:13.023

8

Symbols starting with "@" (e.g. @staticmethod) are called "decorators" in Python jargon.

You can find the PEP describing them at this url.

In short, they are syntactic sugar to invoke a function over the object being decorated, e.g.:

@staticmethod
def myfunc(...): ...

is equivalent to:

def myfunc(...): ...
myfunc = staticmethod(myfunc)

Then, searching on the web for "python decorator" will provide you with a lot of other useful information and use cases.

Hope it helps, ciao

edited Apr 01 '11 at 14:01

answered Apr 01 '11 at 13:55

masterpiga

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Also in the python docs [glossary page](http://docs.python.org/glossary.html#term-decorator) and discussed under [function definitions](http://docs.python.org/reference/compound_stmts.html#function) – coltraneofmars Apr 01 '11 at 14:00

score 4 · Answer 2 · answered Apr 01 '11 at 13:55

4

Python decorators:

http://docs.python.org/reference/compound_stmts.html#function

answered Apr 01 '11 at 13:55

steinar

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score 2 · Answer 3 · answered Apr 01 '11 at 13:54

2

Google for python decorator and you will find enough answers to your question.

answered Apr 01 '11 at 13:54

Ocaso Protal

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score 0 · Answer 4 · answered Apr 01 '11 at 13:57

As other people said, they are decorators. They take the decorated object as an argument and return a new object - which should usually be the same type as the initial one (function or class)

If you do not like the at syntax, you can always write it like that:

@foo
def bar():
    pass

# is the same as:
def bar():
    pass
bar = foo(bar)

Python documentation for @?

4 Answers4