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Date: Sat, 17 Dec 2011 05:25:12 +1100
Subject: Re: Making the case for "typed" lists/iterators in python
From: Chris Angelico <rosuav@gmail.com>
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On Sat, Dec 17, 2011 at 5:05 AM, Roy Smith <roy@panix.com> wrote:
> Most of this was TL:DNR, but I will admit I often wish for a better way
> to log intermediate values. =A0For example, a common pattern in the code
> I'm working with now is functions that end in:
>
> =A0 return [Foo(x) for x in bunch_of_x_thingies]
>
> When something goes amiss and I want to debug the problem, I often
> transform that into:
>
> =A0 =A0temp =3D [Foo(x) for x in bunch_of_x_thingies]
> =A0 =A0logger.debug(temp)
> =A0 =A0return temp
>
> It would be convenient to be able to get at and log the intermediate
> value without having to pull it out to an explicit temporary.

tee =3D lambda func,arg: (func(arg),arg)[1]

return tee(logger.debug,[Foo(x) for x in bunch_of_x_thingies])

ChrisA