Re: Is there any nice way to unpack a list of unknown size??

[Fredrik Lundh]

srinivasan srinivas wrote:

I want to do something like below:

1. first, second, third, *rest = foo

2. for (a,b,c,*rest) in list_of_lists:

update to Python 3.0 (as others have pointed out), or just do

first, second, third = foo[:3]
rest = foo[3:]

for item in list_of_lists:
a, b, c = item[:3]
rest = item[3:]
...

and move on to more interesting parts of your program.

</F>

[Grant Edwards]

On 2008-09-14, Fredrik Lundh <fr*****@pythonware.comwrote:

>1. first, second, third, *rest = foo

2. for (a,b,c,*rest) in list_of_lists:

update to Python 3.0 (as others have pointed out), or just do

first, second, third = foo[:3]
rest = foo[3:]

Of course you can do that in one line if you want it to look a
bit more like the original pseudocode:

(a,b,c),rest = foo[:3],foo[3:]

That still requires you to manually count the number of
"non-rest" destination elements on the LHS and type that number
twice on the RHS. If you wanted to elminate a tiny bit of the
redundancy you could define a split() function:

def split(seq,n):
return seq[:n],seq[n:]

(a,b,c),rest = split(foo,3)

--
Grant