Tuple Syntax and ()

[James Stroud]

tactics40 at gmail.com wrote:
> I keep accidently trying to declare t-tuples as mytuple = (myitem)
> 
> I know this doesn't work and that you need the trailing comma, but
> reading something online, I just came to realize.... the parenthesises
> don't have any special meaning in relation to tuples at all, do they?
> 

Aside from grouping, they are special to construct an empty tuple.

py> () == tuple()
True

Also, don't underestimate their relationship with tuples when it comes 
to grouping:

py> a, b, c = 1, 2, 3
py>
py> a == a, b, c
(True, 2, 3)
py> a == (a, b, c)
False

James

-- 
James Stroud
UCLA-DOE Institute for Genomics and Proteomics
Box 951570
Los Angeles, CA 90095

http://www.jamesstroud.com/