Obscurities was a bad choice in title, methinks….title about question marks seemed hokey.

I tend to use the conditional operator fairly sparingly. The slightest amount of complexity in the statements kills any readability the operator gives me.

I only ask that for folks that tell me they’re experts. If anyone tells me they’re an expert in anything, I’ll test the limits of their knowledge.

I like to see the reactions to threats on egos. Humility and patience coupled with passion are what I look for. I don’t care if they know what it means, I like to see if they react negatively “oh NO ONE uses THAT feature! Ask me a GOOD question!” or positively “Hmmm I’ve never seen that. Here’s where it might be good, here’s where it might be bad.” That tells me plenty if I can trust them to be in front of a customer or not.

If I ever proclaim myself an expert, I hope someone else has the kindness to knock me down a few notches.

DateTime? dateTime = n > 1 null : Datetime.Now;

You must cast the null:
DateTime? dateTime = n > 1 (DateTime?) : DateTime.Now;

Coditional operator, obscure?

Of course, if you put much stock in that as an interview question, I’d be inclined to think you’re just another blow-hard who likes to demonstrate his knowledge about semi-arcane topics during an interview, rather than finding out how qualified an applicant is.

also note that you can divide by zero legitimately, if you use doubles.