Comment on draft PEP for deprecating six builtins

[Bernhard Herzog]

Roman Neuhauser <neuhauser at mail.cz> writes:

> > From: Bernhard Herzog <bh at intevation.de>
> > Why should chr be an int method in the first place? It's not tied to
> > ints all that much[1]. IMO it sits somewhere between ints (including
> > int-like objects !) and strings so it shouldn't be a method of either
> > class. Leaving it a function is perfectly fine, therefore, although
> > putting it into the string module might be a good idea. The same would
> > apply to ord, IMO.
> 
>     Ugh, that looks to me as appropriate as join() being a string
>     method / module function.

Exactly. I still think that join as a function makes more sense than as
a string method and for the same reasons as stated for chr above. Even
if join is implemented as a string method.

> > [1] In fact, chr today accepts any object that can be converted
> > successfully to an int, so that chr(42.5) does work, but that's not
> > always desirable.
> 
>     Any object that can be converted to a character should have a chr()
>     method.

Would the same reasoning apply to objects that can be converted to ints,
for example. I.e. should strings have a method .int() instead of int
taking a string as argument (among other types)? (forgetting for the
moment, that it's actually implemented through the __int__ method :) )

I see numbers and characters as quite different datatypes and a
conversion between the two is right in the middle and neither more on
the int side than on the str side. 

The correspondence between characters depends on an encoding, something
which chr and ord do not take into account at all, for example, and one
couldn't expect that e.g. int knows about encodings, so that a chr
method could take the encoding as argument (perhaps defaulting to
ascii).

Of course, whether a conversion operation should be a method, a function
or a constructor is largely a matter of taste and is influenced by
whatever other languages one is coming from. For someone with a
C-background, characters are ints, so making chr an int method may seem
appropriate from that perspective.

   Bernhard

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