I'm getting
TypeError: 'NoneType' object is not iterable
on this line:
temp, function = findNext(function)
and have no idea why this is failing. I am using function in while loops:
while 0 < len(function):
…
but am not iterating through it. All of the returns in findNext(function) are pretty much
return 'somestring',function[1:]
and cannot understand why it thinks I'm iterating on one of those objects.
I am guessing that findNext falls off the end without returning anything, which makes it automatically return None. Kind of like this:
>>> def findNext(function):
... if function == 'y':
... return 'somestring',function[1:]
...
>>> function = 'x'
>>> print(findNext(function))
None
>>> temp, function = findNext(function)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: 'NoneType' object is not iterable
The solution would be to always return something.
The statement:
return 'somestring',function[1:]
is actually returning a tuple of length 2 and tuples are iterables. It would be more idiomatic to write that statement as:
return ('somestring', function[1:])
which makes its tuple nature far more obvious.
temp, function = findNext(function) but I'm guessing that you are not unpacking consistently. It is hard to tell with the small bits of code you gave.