On 09/06/2016 12:08, Antoon Pardon wrote:
Op 09-06-16 om 12:48 schreef BartC:
What does it matter?
If swap() can be implemented via such a function, then it means that
the language has such capability, which can be useful in different
scenarios.
If it can't, then the language hasn't.
Python doesn't have it so it can't implement swap like that.
There's no need to bring references into it at all.
Whether a language can implement a swap procedure like that is
not the same question as whether the language variables are
references or not.
Now /you're/ turning it around.
I'm not interested in the internal references that Python currently
uses. (I've called them /object references/.)
I'm talking about a different kind of reference, possible /name
references/, they would make possible new things ....
Since the topic was whether or not python has reference variables,
is seems there is no need to bring this swap procedure into it at all,
instead of turning it around and pretending it was about the
swap procedure.
... such as implementing a function that can exchange the values of its
caller's two arguments.
In bytecode, Python might need to swap variables using:
load a
load b
store a
store b
(which can get inefficient if swapping a[i+j-1] and b[j-i+1]). A name
reference would allow:
loadref a
loadref b
swap
--
Bartc
--
https://mail.python.org/mailman/listinfo/python-list
