Debugging fail in #Python: I had a generator function:
def them():
for thing in some_things():
yield thing
But I wanted to quickly try changing it to use a helper that returned a list, so I just added that code at the top:
def them():
return them_from_somewhere_else()
for thing in some_things():
yield thing
Took me a while to figure out why `list(them())` was always an empty list.
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RE: https://hachyderm.io/@nedbat/116150179474021938
The answer to the mystery: because my function had a `yield` in it, it was compiled as a generator. But executing the function never ran `yield`, so iterating it produced an empty sequence. The value from the return statement is ignored.
TBH, I know there is a way to get the returned value, but I have never needed to, and I don't know how.
The solution was to delete the code after the return.
