Function that returns a tuple

[Peter Otten]

Baltimore wrote:

> On 17 juin, 11:16, Marcpp <mar... at gmail.com> wrote:
>> On 17 jun, 03:53, Dan Hipschman <d... at linux.ucla.edu> wrote:> On Sat, Jun
>> 16, 2007 at 06:30:26PM -0700, Marcpp wrote:
>> > > Hi, I need to returns a tuple from a function (reads a database)
>> > > Any idea?.
>>
>> > Like this?
>>
>> > def foo():
>> >     return 1, 2, 3, 4
>>
>> Hi, I need to return a tupla like this function:
>>
>>     def BDllids(a):
>>         a = ()
>>         conn = sqlite.connect('tasques.db')
>>         cursor =  conn.cursor()
>>         cursor.execute('SELECT * FROM tasques')
>>         for row in cursor:
>>             a.append (row[0])
>>         return a()
>>
>> I'm doing the correct, method?
> 
> Why is 'a' used as argument of the function ?
> You don't need to put it in argument.
> 
>      def BDllids():
           a = [] # must be a list; tuples don't have an 
                  # append() method
>          conn = sqlite.connect('tasques.db')
>          cursor =  conn.cursor()
>          cursor.execute('SELECT * FROM tasques')

Make that "SELECT yadda FROM tasques", assuming that 'yadda' is the first
column in the table.

>          for row in cursor:
>              a.append (row[0])
>          return a
> 
> But that's the correct method !

Note that the result is now a list, and that is probably the appropriate
data structure; if you needed a tuple you'd have to convert it:
           
           return tuple(a) # easy, obvious, but probably superfluous

Peter