assignment in a for loop

From: "MackS" <mackstevenson@xxxxxxxxxxx>
Date: 16 May 2006 21:36:30 -0700

Hello everyone

Consider the following

l = [1,2]
for i in l:

.... i = i + 1
....

l

[1, 2]

I understand (I think!) that this is due to the fact that in Python
what looks like "assignment" really is binding a name to an object. The
result is that inside the loop I am creating an object with value (i+1)
and then "pointing" the name i at it. Therefore, the object to which i
previously pointed (an element of list l) remains unchanged.

Two brief questions:

1) Is what I wrote above (minimally) correct?

2) Independently of the answer to 1, is there a way for me to assign to
elements of a list inside a loop and without resorting to C-style
ugliness of

for i in range(len(l))
l[i] = l[i] + 1

?

(Note: not using a list comprehension.)

Thanks in advance

Mack

.

Follow-Ups:
- Re: assignment in a for loop
  - From: Ben Finney
- Re: assignment in a for loop
  - From: MackS

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