palindrome iteration

[Roy Smith]

In article <mailman.174.1283114875.29448.python-list at python.org>,
 MRAB <python at mrabarnett.plus.com> wrote:

> On 29/08/2010 21:34, Roy Smith wrote:
> > In article<8dunm7Fv5nU1 at mid.individual.net>,
> >   Gregory Ewing<greg.ewing at canterbury.ac.nz>  wrote:
> >
> >> Steven D'Aprano wrote:
> >>>   I'm not entirely sure what the use-case for swapcase is.
> >>
> >> Obviously it's for correcting things that were typed
> >> in with tHE cAPS lOCK kEY oN bY mISTAKE. :-)
> >
> > So it would seem (http://bugs.python.org/msg94026).
> >
> > It's also useful for when you're looking for a crypto algorithm and
> > rot13 is too strong.
> >
> > It also provides a handy way to write is_alpha()...
> >
> > def is_alpha(c):
> >      return abs(ord(c) - ord(c.swapcase())) == 32
> >
> > print is_alpha('a')
> > print is_alpha('A')
> > print is_alpha('1')
> > print is_alpha('>')
> 
> How is that better than:
> 
> print 'a'.isalpha()
> print 'A'.isalpha()
> print '1'.isalpha()
> print '>'.isalpha()

Think of my post as an implemention of is_reader_humour_impaired().