On Tue, 15 Nov 2005 21:54:07 -0500, Dan Sommers wrote:
> On Wed, 16 Nov 2005 13:12:38 +1100,
> Steven D'Aprano <[EMAIL PROTECTED]> wrote:
>
>> try:
>> for item in obj:
>> do_stuff(item)
>> except TypeError, msg:
>> if msg == "iteration over non-sequence":
>> handle_non_iterator()
>> else:
>> # re-raise the exception
>> raise
>
> But what it do_stuff tries to iterate over a non-sequence?
I can think of two solutions:
(1) Write do_stuff carefully, and test it thoroughly on its own. If there
are no bugs in do_stuff, you can be sure it isn't going to try to iterate
over a non-iterator. This is a good argument for writing small,
encapsulated, easily analysed and debugged pieces of code.
(2) Muck about writing fragile, possibly buggy code:
# untested
try:
for item in obj:
flag = False
try:
do_stuff(item)
except TypeError, msg:
if msg == "iteration over non-sequence":
flag = True
# re-raise the exception
raise
except TypeError, msg:
if flag:
raise
if msg == "iteration over non-sequence":
handle_non_iterator()
else:
raise
I think you can guess where my preference lies.
--
Steven.
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