printing a sequence...

Lonnie Princehouse finite.automaton at
Fri Jul 16 19:53:44 CEST 2004

To clarify what's already been said-

   thing.__str__() is equivalent to str(thing)

   thing.__repr__() is equivalent to repr(thing)

str(some_list) will call repr() for all of the list's items.

You could try:

   print map(str, a)   

   print [str(x) for x in a]

for the desired effect, or you could overload __repr__ instead of __str__

"Florian Preknya" <bolo at> wrote in message news:<cd8a1u$t6d$1 at>...
> Hi everybody,
> I'm relatively new in using Python and I want to perform a simple job: I
> have a list of objects of type A and want to print them to stdout.
> class A:
>     def __init__(self, value):
>         self.value = value
>     def __str__(self):
>         return "value: %d" % self.value
> a = [A(10), A(12), A(2)]
> print str(a)
> I obtain [<__main__.A instance at 0x00767D80>, <__main__.A instance at
> 0x00768698>, <__main__.A instance at 0x00768350>].
> What I want to obtain is [value: 10, value: 12, value: 2].
> I know that if I change the __str__ to __repr__ I obtain what I want, but
> then I will have these informal strings in debuger also, and I do not want
> that.
> Can I write somehow the print statement to force calling the A.__str__
> function?
> Thanks,
> Florian.

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