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newbie python question

newbie python question# Programming - 葵花宝典

c*e2008-01-28 08:01

1 楼

in C i can do,
int i;
int & j = i;
then when i change i's value I will see the change reflected in j as well.
how to do this in python. a quick search around didnt ring any bell.
thx.

c*g2008-01-28 08:01

2 楼

use list or other mutable objects.

【在 c********e 的大作中提到】

: in C i can do,
: int i;
: int & j = i;
: then when i change i's value I will see the change reflected in j as well.
: how to do this in python. a quick search around didnt ring any bell.
: thx.

j*k2008-01-28 08:01

3 楼

怎么转战场了？Perl里面都有reference, python里面没有?

【在 c********e 的大作中提到】

: in C i can do,
: int i;
: int & j = i;
: then when i change i's value I will see the change reflected in j as well.
: how to do this in python. a quick search around didnt ring any bell.
: thx.

c*e2008-01-28 08:01

4 楼

thx

【在 c*****g 的大作中提到】

: use list or other mutable objects.

c*e2008-01-28 08:01

5 楼

picked python to make a quick log parser to do some offline time analysis
and learn something new...

【在 j*****k 的大作中提到】

: 怎么转战场了？Perl里面都有reference, python里面没有?

d*82008-01-28 08:01

6 楼

没有

【在 j*****k 的大作中提到】

: 怎么转战场了？Perl里面都有reference, python里面没有?

r*t2008-01-28 08:01

7 楼

python里面全是by reference吧。

【在 d*******8 的大作中提到】

: 没有

d*82008-01-28 08:01

8 楼

as i knew, only the elements in list and dict are by reference.
for example:
i = [3, 5]
j = i ==> j is [3, 5]
i[1] = 1 ==> i is [3, 1] and j is [3, 1]

【在 r****t 的大作中提到】

: python里面全是by reference吧。

r*t2008-01-28 08:01

9 楼

所有的attribute也是mutable的。你说的这么几种正好就是所有的immutables

r*t2008-01-28 08:01

10 楼

a = [1]
b = a
after this, when you change b[0] to any value, a[0] is also changed
accordingly:
b[0] = 5
assert a[0]==5
b[0] = 'dfadf'
assert a[0]=='dfadf'
这是因为list的元素是mutable的。python全是by reference.

【在 c********e 的大作中提到】

: in C i can do,
: int i;
: int & j = i;
: then when i change i's value I will see the change reflected in j as well.
: how to do this in python. a quick search around didnt ring any bell.
: thx.