tim.one at home.com
Sun Aug 5 23:59:53 CEST 2001
> Actually compile all the main issues into a single post so that
> people would actually have to think to counter it, and all they do
> is ignore it.
I didn't ignore it, but I didn't reply either -- you were carpet-bombing
c.l.py at the time, and were getting plenty of responses. You may wish to
ponder why the anti-PEP contingent also "ignored" it: there were no
responses period, not even a "me too!".
I just looked it over again, and, frankly, it doesn't make much sense.
Starting at the top:
Sent: Wednesday, July 25, 2001 3:27 AM
Subject: Re: Steve Summary of views on the Is-It-Actually-Better?
> I believe PEP0238 is wrong in principle because...
> 1. The fact that mathematicians have had many views on integers
> and division,
Factually incorrect; mathematicians have no disagreement over the meaning of
int/int (it's a rational).
> and the one that is in most non-specialist mindsets
Hard to know what this means, but the idea that the majority of
non-specialists see "2/3" and think "0" is absurd on the face of it, if
that's what it means.
> doesn't meet the pragmatic requirements for several fields of
> mathematics, is understood. That doesn't make the other
> definitions from less demanding, more down-to-earth fields
PEP 238 retains an operator for flooring division (assuming that's what you
> 2. It particularly does not invalidate the practical view which most
> people can easily understand, which is taught to everyone at
> a very early age and which also happens to work extremely well
> for typical programming tasks (not just specialist applications).
PEP 238 doesn't dispute the utility of flooring division (assuming etc).
> Doesn't the pro-pep views insistence on the most pragmatic
> possible definition of discrete integer division seem more than a
> little inconsistent with their sloppy attitude to the much more
> fundamental difference between discrete and continuous
> Just because it isn't the unnecessarily pragmatic (for normal
> programming tasks) field of mathematics that a few people
> subscribe to, it doesn't make it wrong. It is simply from a less
> specialised, more basic and more generally useful field that
> doesn't address the specialist problems of the minority over the
> general day-to-day practicality of the majority.
If that were English, it would be easier to make a response <wink>.
> 3. Practically all programs use discrete integer quantities -
> indices, subscripts, counters, sizes and more - whereas numerics
> is a particular specialist field.
You've got some private definitions for these terms I was never able to
> Making life more awkward for the majority just to suit a few
> specialist fields is not rational. It's the specialists dealing
> with specialist fields who should have to deal with awkward
> special case syntax and semantics - not the everyday user.
The idea that a majority of non-specialists believe 2/3 means 0 has not been
established, and IMO is almost certainly false.
> 4. Discrete measures and continuous measures are not the same thing
> and should not be arbitrarily confused.
PEP 238 suggests two distinct operators in order to reduce confusion(!).
> Discrete integer division makes perfect sense despite the fact
> that specialist fields have outlawed it for specialist reasons
> relating to specialist problems.
Nobody has "outlawed" any meaning for division, "specialist" or otherwise.
> This is much more fundamental than just switching between
> different representations of continuous measures.
"This" doesn't appear to have a sensible referent.
> The pro-pep groups arbitrarily application of continuous measure
> division principles with a discrete integer type is wrong in
> and it is wrong in engineering,
Whether it's velocity = distance/time, or voltage = watts/amps, engineers
rarely have "discrete" division in mind. So "wrong" is wrong here too.
> and it is wrong in programming.
The meaning of division a program needs depends entirely on context. Any
meaning is "wrong" in some programming contexts.
> My use of more practical day-to-day discrete principles for
> discrete integer arithmetic than would be appropriate in field
> theory - or even 16-year-old pure mathematics, I fully agree
> - is not the same thing at all.
Couldn't parse that one.
> 5. Having established that division on the discrete integer type
> should work in the only practical way that makes sense
LOL! I hope that was *meant* to be tongue-in-cheek.
> ... [much more snipped] ...
This is too time-consuming, Steve, and I think it's clear why you didn't get
support for the kinds of arguments above even from the anti-PEP camp.
Code breakage was and remains a strong anti-PEP argument. You once thought
it was supremely important to "do what other scripting languages do", but
anymore. I thought that was a marginal but plausible argument, and still
do. No other anti-PEP argument survived my personal credibility cutoff.
y'rs - tim
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