Another Sets Problem

[Victor Subervi]

On Mon, Dec 28, 2009 at 3:07 PM, Steve Holden <steve at holdenweb.com> wrote:

> Victor Subervi wrote:
> > On Mon, Dec 28, 2009 at 1:41 PM, MRAB <python at mrabarnett.plus.com
> > <mailto:python at mrabarnett.plus.com>> wrote:
> >
> >     Victor Subervi wrote:
> >
> >         Hi;
> >         I'm using python 2.4.3 which apparently requires that I import
> Set:
> >         from sets import Set
> >         I've done this. In another script I successfully manipulated
> >         MySQL sets by so doing. Here's the code snippet from the script
> >         where I was able to call the elements in a for loop:
> >
> >                  if isinstance(colValue[0], (str, int, float, long,
> >         complex, unicode, list, buffer, xrange, tuple)):
> >                    pass
> >                  else:
> >                    try:
> >                      html = "<b>%s</b>: <select name='%s'>" % (col, col)
> >                      notSet = 0
> >                      for itm in colValue[0]:
> >                        try:
> >                          color, number = itm.split(':')
> >                          html += "<option name='%s'>%s</option>" % (itm,
> >         color)
> >                        except:
> >
> >
> >     DON'T USE BARE EXCEPTS!
> >
> >     (There are 2 in your code.)
> >
> >
> > There are times when they are *necessary*.
> >
> Perhaps so, although it's extremely difficult to think of one since the
> exceptions were rationalised. Do you *really* want to catch the
> exception that occurs when the user tries to stop the program with a
> Control-C? Usually nowadays you want
>
>    except Exception:
>
> as the "widest" specification. You don't *normally* want to catch
> SystemExit, KeyboardInterrupt or GeneratorException.
>
> >
> >
> >                          html += "<option name='%s'>%s</option>" % (itm,
> >         itm)
> >          However, when I try that in my current script, the script
> >         fails. It throws no error, but rather just quits printing to the
> >         screen. Here's the code snippet:
> >
> >                      elif types[x][0:3] == 'set':
> >                        for f in field:
> >                          print '<td>%s</td>\n' % (field)
> >                      else:
> >                        print '<td>%s</td>\n' % (field)
> >
> >     [snip]
> >
> >     You're printing the entire field for each value in the field. Is this
> >     intentional?
> >
> >
> > It doesn't matter. The code ceases to execute with the line:
> >
> > for f in field:
> > beno
> >
> Well it looks to me like types[x][0:3] == 'set' and f is empty. That
> wouldn't produce any printed output.
>

It's not empty. I've printed it. But if it were, it would look like this:
set([])
and so this would be left to print:
([])
beno
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