Unbound Local error? How?

[Hari Sekhon]

I've got some code as follows:

import re
re_regexname = re.compile('abc ')

......
...... various function defs
......

def func1():
...
func2()
...

def func2():
if re_regexname.ma tch('abc'):
<do something>

if __name__ == '__main__':
func1()
but this returns the Traceback:

UnboundLocalErr or: local variable 're_regexname' referenced before
assignment
How?

It was declared in the zero level indentation near the top of the
script! I don't understand this, isn't a function supposed to be able to
reference stuff in the containing function or the top level?

[Diez B. Roggisch]

Hari Sekhon wrote:

import re
re_regexname = re.compile('abc ')

.....
..... various function defs
.....

def func1():
...
func2()
...

def func2():
if re_regexname.ma tch('abc'):
<do something>

if __name__ == '__main__':
func1()

The above clearly is not what you have. See the attached version of the
above that works. So - go check for a typo or something like that.

Diez

[Bruno Desthuilliers]

Hari Sekhon wrote:

I've got some code as follows:

import re
re_regexname = re.compile('abc ')

.....
..... various function defs
.....

def func1():
...
func2()
...

def func2():
if re_regexname.ma tch('abc'):
<do something>

if __name__ == '__main__':
func1()
but this returns the Traceback:

UnboundLocalErr or: local variable 're_regexname' referenced before
assignment
this is *not* the traceback. This is only the error message. The
traceback contains all needed informations (or at least all possible
information at this point) to know what happened. But you did not post
the traceback. Nor did you post the minimal runnable code snippet
producing this error.

How?

How could we know ?
--
bruno desthuilliers
python -c "print '@'.join(['.'.join([w[::-1] for w in p.split('.')]) for
p in 'o****@xiludom. gro'.split('@')])"

[Steve Holden]

Hari Sekhon wrote:

Bruno Desthuilliers wrote:

Hari Sekhon wrote:

I've got some code as follows:

import re
re_regexna me = re.compile('abc ')

.....
..... various function defs
.....

def func1():
...
func2()
...

def func2():
if re_regexname.ma tch('abc'):
<do something>

if __name__ == '__main__':
func1()
but this returns the Traceback:

UnboundLocal Error: local variable 're_regexname' referenced before
assignment

this is *not* the traceback. This is only the error message. The
traceback contains all needed informations (or at least all possible
information at this point) to know what happened. But you did not post
the traceback. Nor did you post the minimal runnable code snippet
producing this error.

How?

How could we know ?

sorry, I know it looks like I was being stingy but the traceback was not
that helpful, not without seeing more a huge amount more of the code. I
was trying to abbreviate.

Traceback (most recent call last):
File "./backup.py", line 649, in ?
backup(machine, share)
File "./backup.py", line 364, in backup
backupdir(sourc e,destination)
File "./backup.py", line 398, in backupdir
(dirlist,fileli st) = getdirlisting( source )
File "./backup.py", line 445, in getdirlisting
if re_skip_dirs.ma tch(x):
UnboundLocalErr or: local variable 're_skip_dirs' referenced before
assignment

This doesn't really show that much, I figured the problem was the following:

def getdirlisting() :
re_skip_dirs = re_skip_top_dir s #Here's the culprit

where both these regex compiled objects were declared at the top level,
it seems that the assignment is trying to use the local variable
re_skip_top_dir s which doesn't exist, that's why I'm getting a
traceback, commenting out this line it runs fine.

-h

The error is simply that you are making an assignment *somewhere* inside
your function body, so the compiler is treating the variable as local,
masking the module-level global name. Consequently when you try to read
its value you are told that the local variable has not yet been bound to
a value.

A "global" statement inside the function body will fix the problem. You
could also add a keyword argument (never used except to set a default
for it in the "def" statement).

regards
Steve
--
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