Tuple index

[Steve M]

John Machin wrote:

> 
> Steve M wrote:
>> Hello,
>>
>>         I'm trying to figure out the index position of a tuple
> member.
>> I know the member name, but I need to know the members index
> position.
> 
> Tuples, like lists, don't have members in the sense that they can be
> "named" like t.foo. The only way of referring to them is by index,
> t[4].
> 
>> I
>> know that if I use the statement print tuple[4] that it will print
> the
>> contents of that location. What I don't understand is if I know that
> foo is
>> a member of tuple, how do I get foo's index position.
> 
> You *can't* "know that foo is a member of tuple".
> 
> Consider this:
> 
>>>> foo = 'carol'
>>>> t = (123,456,789,'bob',foo,'ted')
>>>> t[4]
> 'carol'
> 
> Is that what you mean by "foo is a member of t'? Well, it's not. foo is
> a reference to the string 'carol'. t[4] is also a reference to the
> string 'carol'.
> 
> Now read on ...
> 
>>>> foo = 'alice'
>>>> t
> (123, 456, 789, 'bob', 'carol', 'ted')
>>>> t[4]
> 'carol'
>>>>
> 
> Now foo is a reference to the string 'alice'. Nothing to do with t,
> either before or now.
> 
> Have you read the tutorial found at http://docs.python.org/tut/tut.html
> ?

I guess I explained my problem incorrectly. Let me try again.

tuple = ("fred", "barney", "foo")

I know that foo is an element of tuple, but what I need to know is what
the index of foo is, tuple[?]. Hopefully this explains what I'm trying 
do do better. Sorry about the earlier confusion.

Steve