variables preceeded with @

[Thomas Girod]

Hello there.

I recently started looking at turbogears and I found code such as :

class Root(controllers.Root):
@turbogears.expose(html="blog.templates.accueil")
def index(self,**kw):
return dict()


What is this "@" ? I looked around but couldn't find any references to
this syntax.

Thomas

 

[Diez B. Roggisch]

Hello there.

I recently started looking at turbogears and I found code such as :

class Root(controllers.Root):
@turbogears.expose(html="blog.templates.accueil")
def index(self,**kw):
return dict()


What is this "@" ? I looked around but couldn't find any references to
this syntax.

It is called a decorator syntax, and is basically syntactic sugar for the
following:

class Foo(object):
def bar(self):
pass

bar = decorate(bar)

is

class Foo(object):
@decorate
def bar(self):
pass


You can also have parameterized decorators, as the ones in TG:

class Foo(object):
def bar(self):
pass

bar = decorate_with_args("some argument")(bar)

is

class Foo(object):
@decorate_with_args("some argument")
def bar(self):
pass


I suggest you read this to get on speed with decorators:

http://www.phyast.pitt.edu/~micheles/python/documentation.html



Regards,

Diez

 

[Thomas Girod]

Yum, food for thoughts. Thanks Diez.