Re: Stop writing Python 3.5 incompatible code :-)

[Frank Millman]

"Frank Millman"  wrote in message news:n77j78$ld0$1...@ger.gmane.org...
cur.execute(...)
try:
    row = next(cur)
except StopIteration:
    # 0 rows returned
try:
    next(cur)
except StopIteration: pass
else:
    # >1 rows returned

For the record, I just tried this and found an error.

It is easier to explain if I change it slightly -

cur.execute(...)
try:
   row = next(cur)
except StopIteration:
   # 0 rows returned
try:
   next(cur)
except StopIteration:
   # instead of pass, do something with row
else:
   # >1 rows returned

'do something with row' is reached even if the first next() failed, so row 
does not exist.

Here is the corrected version -

cur.execute(...)
try:
   row = next(cur)
except StopIteration:
   # 0 rows returned
else:
   try:
       next(cur)
   except StopIteration:
       # do something with row
   else:
       # >1 rows returned

Frank


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