[Python-Dev] default of returning None hurts performance? (original) (raw)

Greg Ewing greg.ewing at canterbury.ac.nz
Wed Sep 2 00:04:46 CEST 2009

Xavier Morel wrote:

I fail to grasp the unpredictability of "the last expression evaluated in the body of a function is its return value".

It's unpredictable in the sense that if you're writing a function that's not intended to return a value, you're not thinking about what the last call you make in the function returns, so to a first approximation it's just some random value.

I often write code that makes use of the fact that falling off the end of a function returns None. This has been a documented part of the Python language from the beginning, and changing it would break a lot of code for no good reason.

-- Greg

More information about the Python-Dev mailing list