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Python decorators: A neat way to modify functions (kember.net)
4 points by fogus 1849 days ago | hide | past | web | 2 comments | favorite



It is a crying shame that this article fails to realize that decorator.decorator is itself a decorator, and that failing to use it as such undermines the premise that decorators are "a neat way to modify functions". With this realization:

    @decorator.decorator
    def heading1(func, *args, **kwargs):
        return "<h1>" + func(*args, **kwargs) + "</h1>"
With this construction, you no longer need to have the two copies of the function: the degenerate wrapper can be removed and replaced with this decorator.

Even if the library didn't provide this, you can just look at this code and feel "no, wait, this is wrong: this should be implemented with a decorator" and write this:

    def better_decorator(function):
        def wrapped(function, *args, **kw):
            return decorator.decorator(function, *args, **kw)
        return decorator.decorator(wrapped, function)
This new decorator, @better_decorator, can now be used in place of @decorator.decorate in the above example, and again solves the problem of the degenerate wrapper by generalizing it into a single universal degenerate wrapper.


A crying shame indeed. Thanks for taking the time to point that out and provide such detailed criticism - much appreciated. I've updated the article and credited you.




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