moving items in a list

[andy]

On Tuesday 07 Jan 2003 9:50 pm, Skip Montanaro wrote:
>     ...
>     Mark>         j = i - 1
>     Mark>         swap_with = l[j]
>     Mark>         l[i] = swap_with
>     Mark>         l[j] = item
>     ...
>
> How about
>
>     l[i-1], l[i] = l[i], l[i-1]
>
> ?  It's visually simpler than using a temporary variable and captures the
> sentiment better I think.
>
> Skip

Ug?  You just broke one of my longest-standing programming diktats, ever since 
my college tutor asked us 'anybody know a way to swap the contents of two 
variables?'

Everybody started off saying something like:

	a=b
	b=a

and then realised how stupid that was...

And that was, er, about 20 years ago.  I've never seen a language that could 
do that any better without a 'swap' function.  

a,b=b,a  # how much more obvious can you get?

Just goes to show that you need to talk to people about Python - just applying 
what you already know from (even 20+ years of) programming experience IS NOT 
ENOUGH.  That would never have occurred to me...

-andyj