.join() question

Re: .join() question


"drs" <drs@ecp.cc> wrote in message
news:eo_Oa.1441 5$BM.4645038@ne wssrv26.news.pr odigy.com...[color=blue]
> why does
>[color=green][color=darkred]
> >>> ''.join(lst)[/color][/color]
>
> not automatically do
>[color=green][color=darkred]
> >>> ''.join([str(i) for i in lst])[/color][/color]
>
> ? That is, is there ever a time when one does not want .join to[/color]
make[color=blue]
> everything into a string? This seems like reasonable default[/color]
behavior, but[color=blue]
> maybe I'm missing something?[/color]

If the members of lst are already str strings, this would be a waste
of time. If they are unicode strings, this would be the wrong thing
to do. Auto conversions are not Python's style.

Terry J. Reedy

Re: .join() question

I would risk a guess that this comes under the "explicit is better than
implicit" guideline.

''.join([str(i) for i in lst])

Explains to everyone that you know the list has some non-string things,
and you intend them to be str()'ified.

Intention-guessingly yours,
Simon.

"drs" <drs@ecp.cc> wrote in
news:eo_Oa.1441 5$BM.4645038@ne wssrv26.news.pr odigy.com:
[color=blue]
> why does
>[color=green][color=darkred]
>>>> ''.join(lst)[/color][/color]
>
> not automatically do
>[color=green][color=darkred]
>>>> ''.join([str(i) for i in lst])[/color][/color]
>
> ? That is, is there ever a time when one does not want .join to make
> everything into a string? This seems like reasonable default
> behavior, but maybe I'm missing something?
>
> -doug
>
>
>[/color]

Re: .join() question

"Terry Reedy" <tjreedy@udel.e du> wrote in message
news:Q4KcnQcI8s gt65GiXTWJiA@co mcast.com...[color=blue]
>
> "drs" <drs@ecp.cc> wrote in message
> news:eo_Oa.1441 5$BM.4645038@ne wssrv26.news.pr odigy.com...[color=green]
> > why does
> >[color=darkred]
> > >>> ''.join(lst)[/color]
> >
> > not automatically do
> >[color=darkred]
> > >>> ''.join([str(i) for i in lst])[/color]
> >
> > ? That is, is there ever a time when one does not want .join to[/color]
> make[color=green]
> > everything into a string? This seems like reasonable default[/color]
> behavior, but[color=green]
> > maybe I'm missing something?[/color]
>
> If the members of lst are already str strings, this would be a waste
> of time. If they are unicode strings, this would be the wrong thing
> to do. Auto conversions are not Python's style.[/color]
[color=blue][color=green][color=darkred]
>>> l = [u'abcde', 'fghij']
>>> ''.join(l)[/color][/color][/color]
u'abcdefghij'

this seems to be auto converting the non-unicode to unicode?

-d