Raymond Hettinger wrote:
> [Ron Adam]
>>Currently we can implicitly unpack a tuple or list by using an
>>assignment. How is that any different than passing arguments to a
>>function? Does it use a different mechanism?
> It is the same mechanism, so it is also only appropriate for low
> volumes of data:
> a, b, c = *args # three elements, no problem
> f(*xrange(1000000)) # too much data, not scalable, bad idea
> Whenever you get the urge to write something like the latter, then take
> it as cue to be passing iterators instead of unpacking giant tuples.
Ah... that's what I expected. So it better to transfer a single
reference or object than a huge list of separated items. I suppose that
would be easy to see in byte code.
In examples like the above, the receiving function would probably be
defined with *args also and not individual arguments. So is it
unpacked, transfered to the function, and then repacked. or unpacked,
repacked and then transfered to the function?
And if the * is used on both sides, couldn't it be optimized to skip the
unpacking and repacking? But then it would need to make a copy wouldn't
it? That should still be better than passing individual references.