x, = y (???)

Erik Max Francis max at alcyone.com
Thu Jul 17 21:19:29 CEST 2008

kj wrote:

> I just came across an assignment of the form
>   x, = y
> where y is a string (in case it matters).
> 1. What's the meaning of the comma in the LHS of the assignment?
> 2. How could I have found this out on my own?
> (Regarding (2) above, I consulted the index of several Python
> reference books but I could not find the answer to (1).  I hope to
> find a better Python reference!)

It's unpacking a 1-tuple:

	(x,) = y

The parentheses here are not necessary and are sometimes left out.

Erik Max Francis && max at alcyone.com && http://www.alcyone.com/max/
  San Jose, CA, USA && 37 18 N 121 57 W && AIM, Y!M erikmaxfrancis
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