As others have noted, it's not immediately clear that q{} == 0. Some applications might be happier to throw a fatal exception if numeric input was expected and the empty string given. Others, such as yours, would rather consider it zero. To emit a warning is a reasonable default.

As usual, when I see a contrived example, I want to ask about the real application. Contrived examples are sometimes okay but in this case, the reason for evaluating empty strings arithmetically is missing. Why was this thought necessary? How are these empty strings really being generated? What is the real significance of emptiness here (or, should I say, there)?

Without seeing the real code I can't say; but I'd hazard that if I did, I'd want to offer some advice about something other than the typecasting itself.

In reply to Re: converting strings to ints by Xiong
in thread converting strings to ints by 7stud

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