I did a code assignment for a potential JavaScript heavy job in 2014, for some reason I think isNaN was part of the language then because I have a memory deciding not to use it (but could be misremembering), at any rate I did Number(x) !== Number(x) at some point.
In the meeting when they went over the code the guy who did it said we were wondering why you did this? So I had to explain NaN to him. He really did not know it existed. At any rate I thought this is a weird thing not to know anything at all about.
Comments
I did a code assignment for a potential JavaScript heavy job in 2014, for some reason I think isNaN was part of the language then because I have a memory deciding not to use it (but could be misremembering), at any rate I did Number(x) !== Number(x) at some point.
In the meeting when they went over the code the guy who did it said we were wondering why you did this? So I had to explain NaN to him. He really did not know it existed. At any rate I thought this is a weird thing not to know anything at all about.
Related: I’ve met developers who think NaNs are a language or library (notably pandas) feature.