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    If you are wrapping it with a method, at least catch StopIteration and raise EmptySequence error. Would be much prettier when there are no elements.
    – Guy
    Commented Jan 26, 2018 at 3:28
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    @guyarad StopIteration is the canonical "out of elements" exception in python. I don't see a problem with it being thrown. I'd probably use a default of "None" which can be passed in as a default parameter to the function.
    – Baldrickk
    Commented May 24, 2018 at 7:51
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    Baldrickk I feel like this isn't an iteration method. You won't call this one in a contest of an iterator. But I'm not feeling too strongly about it :)
    – Guy
    Commented May 25, 2018 at 12:45
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    There should be an optional default argument, and if that argument not be supplied, only then raise an exception when no element in the sequence satisfy the condition.
    – Zorf
    Commented Feb 26, 2020 at 22:39
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    Yep! The other thing you'll want to do here is test whether condition exists before trying to write a condition; sometimes even returning x at all from an iterator could be expensive (e.g., if x is a generator yield). So check if condition otherwise just return next(x for x in iterable, default)
    – brandonscript
    Commented Apr 11, 2021 at 23:31