Re: Exec Statement Question

[Victor Subervi]

On Sun, Nov 29, 2009 at 10:23 PM, Dave Angel <da...@ieee.org> wrote:

> exec is a statement, and statements don't have "return values."   It's not
> a function, so there are no parentheses in its syntax, either.  exec is also
> a technique of last resort;  there's nearly always a better/safer/faster way
> to accomplish what you might want, but of course you don't say what that is.
>
> As for "returning" values, exec by default uses the same global space as
> your app, so you can just modify a global variable in your "called" code and
> use it afterwards.
>
> abc = 42
> value = 12
> exec "abc = %d" % value
> print abc
>

Taking out the parenthesis did it! Thanks. Now, you state this is an option
of last resort. Although this does indeed achieve my desired aim, here is a
complete example of what I am trying to achieve. The following is from
'createTables2.py':

  for table in tables:
    try:
      exec 'from options import %s' % table
    except:
      pass
    try:
      exec '%s()' % table
    except:
      pass


The following is from 'options.py':

def jewelry(which=''):
  code = []
  names = []
  meanings = []
  code.append(['5', '5&frac12;', '6', '6&frac12;', '7', '7&frac12;', '8',
'8&frac12;', '9', '9&frac12;', '10', '10&frac12;', '11', '11&frac12;', '12',
'12&frac12;', '13', '13&frac12;'])
  meanings.append('The standard ring sizes.')
  names.append('ringSizes')
  code.append(['Petite (7&#34;)', 'Average (7&frac12;&#34;)', 'Large
(8&#34;)', 'Extra-large (8&frac12;&#34;)'])
  meanings.append('The standard bracelet sizes.')
  names.append('braceletSizes')
  code.append(['16&#34;', '18&#34;', '20&#34;', '22&#34;', '24&#34;'])
  meanings.append('The standard necklace sizes.')
  names.append('necklaceSizes')
  code.append(['14K gold', '18K gold', 'silver', '14K white gold', '18K
white gold', 'platinum', 'tungsten', 'titanium'])
  meanings.append('The standard jewelry metals.')
  names.append('metals')
  code.append(['diamond', 'emerald', 'ruby', 'sapphire', 'pearl', 'opal',
'topaz', 'onyx', 'lapiz lazuli', 'tanzanite', 'garnet', 'quartz', 'rose
quartz', 'amethyst', 'alexandrite', 'peridot', 'tourmaline', 'citrine',
'turquoise'])
  meanings.append('The standard jewelry stones.')
  names.append('stones')
  if which == '':
    i = 0
    all = ''
    while i < len(meanings):
      table = '%s\n' % meanings[i]
      table += "<table>\n <tr>\n  <td colspan='8' align='center'>%s</td>\n
</tr>" % names[i]
      j = 0
      for elt in code:
        if (j + 8) % 8 == 0:
          table += ' <tr>\n'
        table += '  <td>%s</td>\n' % code[i]
        if (j + 8) % 8 == 0:
          table += ' </tr>\n'
        j += 1
      if table[-6:] != '</tr>\n':
        table += ' </tr>\n'
      table += '</table>\n'
      all += table + '<br /><br />'
      i += 1
    print all

This all works fine; however, if there is a better way of doing it, please
let me know.
Thanks,
V

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