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stacked decorators and consolidating

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Date Tue, 29 Oct 2013 11:54:27 -0500
From Tim Chase <python.list@tim.thechases.com>
To python-list@python.org
Subject stacked decorators and consolidating
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I've got some decorators that work fine as such:

  @dec1(args1)
  @dec2(args2)
  @dec3(args3)
  def myfun(...):
    pass

However, I used that sequence quite a bit, so I figured I could do
something like

  dec_all = dec1(args1)(dec2(args2)(dec3(args3)))

to consolidate the whole mess down to

  @dec_all
  def myfun(...):
    pass

However, this yields different (test-breaking) results.  Messing
around, I found that if I write it as

  dec_all = lambda fn: dec1(args1)(dec2(args2)(dec3(args3)(fn)))

it works and passes all preexisting tests.

What am I missing that would cause this difference in behavior?

-tkc



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stacked decorators and consolidating Tim Chase <python.list@tim.thechases.com> - 2013-10-29 11:54 -0500

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