In my opinion you are mostly describing Scala. Mutability and impurity is trivially easy to do in Scala. You may see that as a positive or a negative. Local mut

In my opinion you are mostly describing Scala. Mutability and impurity is trivially easy to do in Scala. You may see that as a positive or a negative. Local mutability is definitely easier. Complexity of Scala comes from mixing OO and FP worlds and I think it's an amazing engineering feat. It will undoubtedly look ugly after you do Haskell though.