They scoff: "of course it's possible; you just..." and it's something you've tried, and you show them why it doesn't work. They laugh it off: "well then you just..." and again. Perhaps a few more times. And ultimately they concede that you're right, there just isn't a way to do it.
You are disappointed, of course, that there isn't a good solution; and you're satisfied, of course, that you weren't mistaken, and that the people who were telling you you were were wrong. Even upon reflection, you can't tell which predominates.
I am naming this feeling "haskell".