I have job interview scheduled early tomorrow. Due problems out of my control (railway on strike while returning from the conference in another city ) I will be at home very late today. I still can make into the interview, and would be OK for generic chat, but if they start programming assignments (that is probable), lack of sufficient sleep will obviously decrease my performance. How bad would be to say I would rather come any day later? The interview is early; in the morning they would find my "sorry" email instead of me.
This late in the game, if there is any way you could make it, then do show up. You only want to cancel at the last moment if there is absolutely no way to make the interview.
Do mention the challenge that you ran into and that you wanted to show up rather than inconvenience everyone by rescheduling at the last minute. This will show your commitment and willingness to give it your best, which the hiring committee will hopefully recognize and appreciate.
If they do not, well that's an indication of things to come, potentially, after you begin work...so you can draw some conclusions. Good luck!
Go to the interview, it's too short notice to do anything else. I'm sure they're aware of the strike and everything else going on. Any weakness in programming will have that as an obvious excuse.
Showing up despite difficult circumstances would impress me more than some fogginess would discourage me. I'm sure your interviewer would feel the same