computing with characters

[Duncan Booth]

George Sakkis <george.sakkis at gmail.com> wrote:

> On Apr 30, 5:06 am, Torsten Bronger <bron... at physik.rwth-aachen.de>
> wrote:
>> Hallöchen!
>>
>> SL writes:
>> > "Gabriel Genellina" <gagsl-... at yahoo.com.ar> schreef in bericht
>> >news:mailman.365.1209541507.12834.python-list at python.org...
>>
>> >> En Wed, 30 Apr 2008 04:19:22 -0300, SL <n... at hao.com> escribió: 
And
>> >> that's a very reasonable place to search; I think chr and ord are
>> >> builtin functions (and not str methods) just by an historical
>> >> accident. (Or is there any other reason? what's wrong with
>> >> "a".ord() or str.from_ordinal(65))?
>>
>> > yes when you know other OO languages you expect this. Anyone know
>> > why builtins were chosen? Just curious
>>
>> *Maybe* for aesthetical reasons.  I find ord(c) more pleasent for
>> the eye.  YMMV.
>>
>> The biggest ugliness though is ",".join().  No idea why this should
>> be better than join(list, separator=" ").  
> 
> Seconded. While we're at it, a third optional 'encode=str' argument
> should be added, to the effect of:
> 
> def join(iterable, sep=' ', encode=str):
>     return sep.join(encode(x) for x in iterable)
> 
> I can't count the times I've been bitten by TypeErrors raised on
> ','.join(s) if s contains non-string objects; having to do
> ','.join(map(str,s)) or ','.join(str(x) for x in s) gets old fast.
> "Explicit is better than implicit" unless there is an obvious default.
> 
I'm afraid I don't agree with you on this. Most places where I use join 
I already know the type of the values being joined. In those few cases 
where I want to join non strings, or want to do some other processing on 
the values the generator comprehension is easy and has the advantage 
that I can use a more complex expression than a simple function call 
without having to wrap it in a lambda or otherwise contort things:

e.g. comma.join(x[1] for x in s)
vs.  comma.join(s, encode=operator.itemgetter(1))
or   comma.join(s, encode=lambda x: x[1])

Plus of course, you aren't going to be writing ','.join(str(x) for x in 
s) more than once in any given program before you extract it out to a 
function, are you?