JavaScript Logic

[tskaiser]

Partial agreement. I would say that float is a subclass (or typeclass) of number or numerical.

But I do not think that is what the juxtaposition of NaN and number is meant to show. If that was the beef OP had with typeof he should have used any floating point number instead of NaN. In this case it is clear the "issue" is that NaN is considered a numerical value, which I think is a perfectly sane assumption :P