Can anyone explain why "begin B: 123" prints, but 456 doesn't?
$ /usr/bin/python2.3 x1x2.py
begin A:
Pre B: 123 456
begin B: 123
Traceback (most recent call last):
File "x1x2.py", line 13, in ?
A()
File "x1x2.py", line 11, in A
B()
File "x1x2.py", line 7, in B
print "begin B:",x1,x2
UnboundLocalError: local variable 'x2' referenced before assignment
$ cat x1x2.py
#!/usr/bin/env python
def A():
print "begin A:"
x1=123;
x2=456;
def B():
print "begin B:",x1,x2
x2 = x2 - 1; # comment out this line and script x1x2 magically
works!!
print "end B:",x1,x2
print "Pre B:",x1,x2
B()
print "end A:",x1,x2
A()
$ /usr/bin/python2.3
Python 2.3.4 (#1, Mar 10 2006, 06:12:09)
[GCC 3.4.5 20051201 (Red Hat 3.4.5-2)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>>
$ /usr/bin/python2.3 -V
Python 2.3.4
$ /usr/local/bin/python2.4 -V
Python 2.4.2
$ /usr/local/bin/python2.4 x1x2.py
begin A:
Pre B: 123 456
begin B: 123
Traceback (most recent call last):
File "x1x2.py", line 13, in ?
A()
File "x1x2.py", line 11, in A
B()
File "x1x2.py", line 7, in B
print "begin B:",x1,x2
UnboundLocalError: local variable 'x2' referenced before assignment
# I compiled up 2.4 from the FC4 source, but 2.3 was from SL4.3
$ python -V
Python 2.4.2
$ python
Python 2.4.2 (#1, Aug 15 2006, 21:51:33)
[GCC 3.4.5 20051201 (Red Hat 3.4.5-2)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>>
$
--
http://mail.python.org/mailman/listinfo/python-list
