Ints and performance (was Re: PEP0238 lament)

[Terry Reedy]

> That is my point, though.  These integer optimizations are, as we
> agree, a clear win.  Are these optimizations in danger of being
impacted
> as a result of this unification, or will we still be able to count
> on integer performance being significantly better than that of
> less frequently used types.

I agree with this concern.  I would say it thus (especially for Tim
and Guido), with some rough numbers:

We agree that the 10 to 1 gain in programming speed often to usually
makes up for the 100 to 1 loss in execution speed (or we would not be
using Python).   But it would not as often make up for a 10000 to 1
loss (if such resulted from some fancy unification scheme).  Since we
love Python so much, we would *prefer* not to have to recalculate the
tradeoff and have to choose between options such as a) convert more
code to embedded C, which for many would be a first-time experience;
b) stick with the last 'fast' Python; c) support a parallel 'fast'
Python version; or d) (gasp!) investigate other languages.

Terry J. Reedy