python needs leaning stuff from other language

Robert Kern robert.kern at gmail.com
Sat Apr 4 03:03:07 EDT 2009


On 2009-04-03 23:48, Tim Wintle wrote:
> On Fri, 2009-04-03 at 18:27 -0500, Robert Kern wrote:
>>> agreed. If .clear was to be added then really assignments to slices
>>> should be entirely removed.
>> Please tell me you are joking.
>
> Well I'm not joking as such.
>
> I've noticed that python-ideas seems to be positive on the idea, and has
> a patch ready for Guido, obviously I'm not that anti it that I'd always
> be complaining if it is implemented, I just see it as unnecessary:
> http://mail.python.org/pipermail/python-ideas/2009-April/003933.html

Let's be clear: python-ideas seems positive on the idea of adding a .clear() 
method. *Completely removing* slice assignment has not been broached there.

> (I didn't expect such strong responses btw!)

You are proposing the removal of a general, orthogonal feature (and breaking 
code in consequence!) just because of a new syntax for a single special case of 
that feature. That is quite simply ridiculous.

.clear() would be non-orthogonal syntactic sugar. That's okay! Python has 
syntactic sugar in a number of other places, too! Appropriate doses of syntactic 
sugar and non-orthogonality are precisely what lets you implement "There should 
be one-- and preferably only one --obvious way to do it." The really key word in 
that sentence is "obvious", not "one".

FWIW, removing slice assignment would be a gross form of non-orthogonality, too. 
__getitem__, __setitem__ and __delitem__ should all be able to accept the same 
indices (or else raise exceptions in the case of immutability).

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco




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