Python Decorator

gistfile1.py

__author__ = 'Christoph Gerneth'
'''
Decorators are one of the most powerful patterns. They can be used to
inject code in functions, modify them and infuence their beihavior.
[wikipedia](https://en.wikipedia.org/wiki/Decorator_pattern)
Here is an example:
'''
class Tools(object):
  @classmethod
  def sayhello(self, func):
    def decorated(*args, **kwargs):
      #excecute the decorated function:
      result = func(*args, **kwargs)
      #modify the restul here...
      result = ' '.join(('Hello', str(result), 'some aditional foo'))
      return result
    #return the modified function. This is not a call!
    return decorated


#Ok, now we decorate the targetfunction:
@Tools.sayhello
def dosomething(name):
  #whatever-code
  return name.upper()

# ...and execute it.
print dosomething("Christoph")

# the result is "Hello CHRISTOPH some aditional foo"