> Dependent types seem like they would have to be explicitly static
Right, because they lift values into type system, those values need to be well-typed themselves. You wouldn't be able to represent gradually typed dynamic/Any value then, I think. I might be wrong though, my understanding of type theory is limited at best :)
> to get proper optimization and reduce the overhead of dynamic checking and conversion
That's probably why very few gradual type systems are taken advantage of when optimizing. Typed Racked does this, but Typed Racket disallows untyped values within the typed module. Hack probably does it, too, but I have no experience using it. Common Lisp does it with correct optimization settings. Raku does this, but Raku was written from the ground up with gradual typing in mind. There are projects that try to transpile fully-typed subsets of dynamic languages to C (can't find the link right now), but that's a bit different. Other popular gradual type systems are basically advanced linters. There's a lot of development and potential in this area though, we'll see how it pans out in a few years :)
Right, because they lift values into type system, those values need to be well-typed themselves. You wouldn't be able to represent gradually typed dynamic/Any value then, I think. I might be wrong though, my understanding of type theory is limited at best :)
> to get proper optimization and reduce the overhead of dynamic checking and conversion
That's probably why very few gradual type systems are taken advantage of when optimizing. Typed Racked does this, but Typed Racket disallows untyped values within the typed module. Hack probably does it, too, but I have no experience using it. Common Lisp does it with correct optimization settings. Raku does this, but Raku was written from the ground up with gradual typing in mind. There are projects that try to transpile fully-typed subsets of dynamic languages to C (can't find the link right now), but that's a bit different. Other popular gradual type systems are basically advanced linters. There's a lot of development and potential in this area though, we'll see how it pans out in a few years :)