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Not all static type systems are equally expressive/safe/consistent - Java falls back to `Object` and runtime casts frequently, Go doesn't have enums, and C++ variants come with significant footguns and ergonomics issues since they were hacked on and aren't first class language features (i.e. safe access requires using `try/except` which is exclusive with other control structures).

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> Java falls back to `Object` and runtime casts frequently

Is it frequently? Generics are definitely not as nice as they could be, but they are surprisingly "sufficient" for almost any library, e.g. a full on type-safe SQL DSL like JOOQ. Unsafe casts are very rare, and where you do need Object and stuff are very dynamic stuff where it's impossible to extend compile-time guarantees even theoretically (e.g. runtime code generation, dynamic code loading, etc - people often forget about these use cases, not everything can work in a closed universe)

jOOQ's internals are full of unsafe casts, though.

Well, you have basically implemented a Java type-system level type checker for SQL. I don't believe there is any type system strong enough to express the whole thing without the escape hatches (casts), besides Lean, Coq and alia.

Not sure what you mean. I meant that without declaration site variance, ("pragmatic") unsafe casting is everywhere in jOOQ's internals. Without being able to capture wildcards in local type variables, ("pragmatic") rawtypes are everywhere as well (check Collections.swap() for an illustration)

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