I was expecting/hoping to learn something new, and instead only came to this same realization. The most I could say is that interfaces/etc can sometimes give a

I was expecting/hoping to learn something new, and instead only came to this same realization. The most I could say is that interfaces/etc can sometimes give a false sense of (type) safety. On finding the cause of such a fault, I don't shake my fist at interfaces, I say "Doh! I should know better." > Some responders seemed surprised by this idea, and I thought this was common knowledge but could not find any blog posts about it either. I figured maybe it was worth writing out, and some people agreed, so here we are: The idea is both surprising and common knowledge. Surprising to think that it's a special kind of type weakness, rather than a common one where actual cases are not surprising at all. Nice writing, more substantial content would be great! If we take away all the big words, use Java instead of Haskell/Rust and start with the example that breaks, it would be a much shorter post that no one would care to read. I don't know that the great writing and build-up is worthwhile, other than a pleasant if somewhat disappointing read.