How to apply decorators to lambdas?

Question

Is there any syntax for using a decorator on a lambda function in Python? Example:

def simpledecorator(f):      def new_f():          print "Using a decorator: "          f()      return  new_f  @simpledecorator def hello():     print "Hello world!" 

Results in this output:

>>> hello() Using a simple decorator: Hello world! 

Yet when I try the same with a lambda:

@anotherdecorator f = lambda x: x * 2 

I get this:

  File "<stdin", line 2     f = lambda x: x * 2     ^  SyntaxError: invalid syntax 

I feel like this might be a good way to make lambdas more versatile by allowing statements to be "injected" into them. But if there exists such a feature, I don't know what the syntax is.

Answer 1

f = anotherdecorator(lambda x: x * 2) 

Answer 2

There appear to be two options which give the functionality, but without the clean syntax:

(1) Keep lambda and ditch the decorator syntax (as posted by dan04):

f = simpledecorator( lambda : print( "Hello World" ) )

(2) Keep the decorator syntax and use a 1 line def statement instead of lambda:

@simpledecorator def f(): print ( "Hello World" )  

This 2nd form may be preferable if you want to chain decorators:

@simpledecorator @simpledecorator def f(): print ( "Hello World" )