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Comment by miloshasan | Hacker News Reader

Didn't downvote you, but the difference is that lambdas can only be executed (i.e. applied to something) while decorators let you analyze the code of the function and do something else other than just executing it.

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How is this so? Decorators are just syntactic sugar for defining a function then replacing it with the result of calling another function (the decorator) on it.

The decorator can do introspection on the function object. This project uses the idea to execute (some) Python code on the GPU:

http://code.google.com/p/copperhead/

> The decorator can do introspection on the function object.

so can normal (i.e. not using decorators) code after the the function, e.g.:

   def myFunction(x):
      blah
   doSomethingWith(myFunction)

Here, doSomethingWith() can introspect on myFunction()

Ah, yes - of course decorators do not fundamentally increase the expressive power of the language (and neither do lambdas, obviously). It's all just a matter of convenience and elegance, which are in the eye of the beholder anyway...

Which being able to wrap the function definition in a function call could accomplish. Unfortunately that's not the direction the Python team wants to take the language.

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