On Feb 6, 2014, at 22:03, Terry Reedy <tjreedy@udel.edu> wrote:
On 2/6/2014 11:15 PM, Terry Reedy wrote:
On Fri, Feb 7, 2014 at 1:36 PM, Terry Reedy
def __next__(self): try: x = self.func() except Exception as exc: if isinstance(exc, self.sentinel): raise StopIteration from None else: raise
I just realized that the above is unnecessarily complicated because the expression that follows 'except' is not limited to a builtin exception class name or tuple thereof. (I have never before had reason to dynamically determine the exception to be caught.) So, using a third parameter, replace the 5 lines with 2.
except self.stop_exception: raise StopIteration from None
Except that you don't have a stop_exception, you have a sentinel, which can be either an object or an exception type. I'm actually not sure whether it's legal to use, say, 0 or "" as the except expression. In recent 3.4 builds, it seems to be accepted, and to never catch anything. So, if that's guaranteed by the language, it's just a simple typo to fix and your simplified implementation works perfectly.
if x == self.sentinel: raise StopIteration else: return x
-- Terry Jan Reedy
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