[srean]

All I can say is you will learn a little bit more if your "know it all" persona is in proportion with your actual extensive knowledge :)

There was a recent thread on HN on Ousterhout on exactly that https://news.ycombinator.com/item?id=17779953

Re evidence, you cant possibly expect me to replicate the entire software library stack here on HN or elsewhere to show the loss of type information.

Hint you are still looking at functions in isolation and repeating loss of type info cannot happen and I have dealt with hundreds of counter examples. You can look up the conversation, I did not say the pointed Github code is to blame. I pointed the code saying we have to make sure that piece of code is eventually called with the right type. We have to ensure that at the time of creation of the sparse matrices. With the dynamic type handling this gets lost. Int64 gets dropped to Int32.