Problem 12. Fibonacci sequence

Shouldn't be flagged - this is a valid solution.

@Christian, This is flagged for the use of "str2num" to cheat by reducing the solution size, though it does not have bear any such impact now.

I believe it is best to discourage this practice and also inform people not to do so as well, specifically when contributes nothing to the code and can cause trouble given that "str2num" uses" eval".

Oh, I didn't know it used eval, interesting.

I personally feel that since you can't execute arbitrary code with str2num() - in particular, unlike with the usual regexp cheat, you can't hide arbitrary code in it to get to size 10 -, it's valid in golfing.

I'd not recommend doing this in production code, of course, but that goes for pretty much all code golfing practices.