[Python-Dev] cpython: Avoid useless "++" at the end of functions

Terry Reedy tjreedy at udel.edu
Thu May 26 20:22:11 CEST 2011


On 5/26/2011 2:08 PM, Guido van Rossum wrote:

> Sorry to butt in here, but I agree with Eric that it was better
> before. There is a common idiom, *pointer++ =<something>, and
> whenever you see that you know that you are appending something to an
> output buffer. Perhaps the most important idea here is that this
> maintains the *invariant* "pointer points just after the last thing in
> the buffer". Always maintaining the invariant is better than trying to
> micro-optimize things so as to avoid updating dead values. The
> compiler is better at that.

This explanation makes sense (more than Eric's version of perhaps the 
same thing ;-).

http://bugs.python.org/issue12188
"A condensed version of the above added to PEP 7 would help new 
developers see the usage as local idiom rather than style bug."

Terry J. Reedy


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