UI toolkits for Python

[Steve Holden]

Alex Martelli wrote:
> Mike Meyer <mwm at mired.org> wrote:
[... browser audience discussion ...]
>>What makes you think that the expenditure of effort is "totally out of
>>proportion"? In my experience, that isn't the case - at least if you
>>go into it planning on doing things that way. Retrofitting a site that
>>was built without any thought but "make it work in my favoriter
>>browser in my favorite configuration" can be a radically different
>>thing.
> 
> 
> Why, of course -- coding a site to just one browser would be foolish
> (though there exist sites that follow that strategy, it's still
> despicable).  What I'm talking about is sites that are _supposed_ to be
> able to support a dozen browsers, in three or four versions each, not to
> mention a dozen features each of which the user "might" have chosen to
> disable (for a total of 2**12 == 4096 possibilities).  Of course, the
> site's poor authors cannot possibly have tested the 4096 * 12 * 3.5
> possibilities, whence the "_supposed_ to be".
> 
> We ARE talking about moving from supporting 95% to supporting
> (*supposedly*!) 100%, after all -- very much into the long, *LONG* tail
> of obscure buggy versions of this browser or that, which SOME users
> within those last centiles may have forgotten to patch/upgrade, etc.
> And THAT is what makes the effort totally out of proportion (differently
> from the effort to go from 60% to 95%, which, while far from negligible,
> is well within sensible engineering parameters).
> 
> 
> 
>>>Maybe that's part of the explanation for the
>>>outstanding success of some enterprises founded by engineers, led by
>>>engineers, and staffed overwhelmingly with engineers, competing with
>>>other firms where marketing wield power...?
>>
>>You mean like google? Until recently, they're an outstanding example
>>of doing things right, and providing functionality that degrades
>>gracefully as the clients capabilities go down.
> 
> 
> I'm not sure what you mean by "until recently" in this context.  AFAIK,
> we've NEVER wasted our efforts by pouring them into the quixotic task of
> supporting *100%* of possible browsers that may hit us, with the near
> infinite number of combinations of browsers, versions and disabled
> feature that this would require.  One may quibble whether the target
> percentage should be, say, 93%, 95%, or 97%, and what level of
> degradation can still be considered "graceful" around various axes, but
> the 100% goal which you so clearly imply above would, in my personal
> opinion, be simply foolish now, just as it would have been 3 years ago.
> 

In mine, too. It's often useful to remember the so-called 80/20 rule 
which, in software terms, I often state as "you can get 80% of the 
functionality for 20% of the cost". Among other things I theorise that 
this accounts for the vast numbers of abandoned open source projects 
lurking on the Internet (but let's not follow that red herring any further).

Of course, if the final 20% of a project's functionality accounts for 
80% of the cost then the stark arithmetical truth would be that each 
functionality percentage point costs sixteen times what the first eighty 
points did.

In practice the situation is never linear, and the truth is that there 
is a situation of diminishing returns which rarely justifies supporting 
those final additional hold-outs with obsolete platforms. This is as 
much an economic decision as a marketing one, but a good engineer knows 
instinctively that there is a desirable cut-off point beyond which 
adding further functionality is a waste of engineering effort.

regards
  Steve
-- 
Steve Holden       +44 150 684 7255  +1 800 494 3119
Holden Web LLC                     www.holdenweb.com
PyCon TX 2006                  www.python.org/pycon/