[Tutor] list as a first class citizen in python?
Wed, 26 Dec 2001 12:14:17 +0530
I found this quote on the web..regarding python...
Because everything is a reference, and there's no way to dereference
that reference, it turns out that there is no trivial way to copy
a list! This fails:
x = [1,2]
y = x
Because you don't get a new list there, just a copy to an
old one. Suggested work-arounds include
y = x[0:]
y = x[:]
y = x + 
y = x * 1
This forces people to think about references, again.
So much for lists being first class citizens! Compare
this with Perl's
@x = (1,2);
@y = @x;
Or even with references:
$x = [1,2];
$y = [ @$x ];
@y = @$x;
what's wrong with working with a reference.
can someone explain the argument here?
java does a similar thing. In java i would do a clone() to get a copy of an
arraylist and in python i will
if something is a first class citizen , should it support "copying" using
simple assignments ? / how are first class citizens expected to behave ? :-)