[Python-Dev] Is implicit underscore assignment buggy? (original) (raw)

Bob Ippolito bob at redivi.com
Thu Jun 8 01:19:14 CEST 2006

On Jun 7, 2006, at 3:41 PM, Aahz wrote:

On Wed, Jun 07, 2006, Raymond Hettinger wrote:

Fredrik:

for users, it's actually quite simple to figure out what's in the variable: it's the most recently printed result. if you cannot see it, it's not in there. Of course, there's a pattern to it. The question is whether it is the right behavior. Would the underscore assignment be more useful and intuitive if it always contained the immediately preceding result, even if it was None? In some cases (such as the regexp example), None is a valid and useful possible result of a computation and you may want to access that result with . My take is that Fredrik is correct about the current behavior being most generally useful even if it is slightly less consistent, as well as being undesired in rare circumstances. Consider that your message is the only one I've seen in more than five years of monitoring python-dev and c.l.py.

I agree. I've definitely made use of the current behavior, e.g. for
printing a different representation of _ before doing something else
with it.

-bob

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