[Python-Dev] Re: stringobject question

[M.-A. Lemburg]

Moshe Zadka wrote:
> 
> On Wed, 14 Jun 2000, M.-A. Lemburg wrote:
> 
> > > > >>> ''.isdigit()
> > > > 1
> > > > >>> ''.isspace()
> > > > 1
> > > >
> > >
> > > Good point, maybe. The __docs__ say:
> > >
> > > "S.isdigit() -> int\n\
> > > \n\
> > > Return 1 if there are only digit characters in S,\n\
> > > 0 otherwise.";
> > >
> > > static char isspace__doc__[] =
> > > "S.isspace() -> int\n\
> > > \n\
> > > Return 1 if there are only whitespace characters in S,\n\
> > > 0 otherwise.";
> > >
> > > I am not an English language lawyer so I could see both interpretations from
> > > the doc strings. I agree, that the result with a zero length string is
> > > surprising.
> > >
> > > Hi All,
> > > Which should it be? Sorry, if this has been covered.
> >
> > I guess it's a bug... a subtle one though, because in a
> > certain sense both 1 and 0 are acceptable. But since
> > '' is considered to be false, I think that returning 0
> > makes more sense.
> >
> > I'll fix this to return 0 for emtpy strings and Unicode objects.
> 
> I just realized something: if you change the semantics to mean "number of
> digits", you'll get the right answer for all 0- and 1- length strings
> and unicode objects.

Hmm, the .isXXX() tests should return 1/0 since they test
properties rather than count characters.

-- 
Marc-Andre Lemburg
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