>I do dynamic dispatch all the time in strongly typed languages.

I believe semantics is getting in our way of communicating.

You don't do dynamic dispatch ___ALL___ the time. You only do it at runtime. And you only do static type safety at compile time. Those are different times.

You can't have both of those features at the __SAME TME__, therefore you can't have both features ALL the time. They are mutually exclusive.

"All the time" is an english expression, please, look it up before going all-caps Python name mangle convention on me.

Yes, of course dynamic dispatch is a runtime phenomenom, that's the dynamic part of it. But there's nothing stopping the code that performs dynamic dispatch from being strongly typed. Strong types are instructions used to prove that the code holds certain properties, they are a separate program from the final binary the compiler gives you. Do you also think that code that gets unit tested can't perform dynamic dispatch?

If your point is that "types don't exist at runtime anyway" (reflection aside) then you don't understand what the purpose of a type system is, nor what strongly typed code means.

> "All the time" is an english expression, please, look it up before going all-caps Python name mangle convention on me.

I know reaction comments are discouraged on HN, but this had me in stitches. Top-tier gourmet dig right there.

There is something stopping you from running the proof against your implementation!

Proof-checking happens only at compile time.

The implementation that you want to prove things about is only available at runtime!

Non-availability (incompleteness) of information is what is preventing you…

Dynamic dispatch is literally a runtime feature of a language. That's why it's called "dynamic". GP can absolutely use dynamic dispatch "all the time" in the sense that they use it regularly in their program, perhaps in every or nearly every program they write.

Your statement is verging on the nonsensical, like saying to someone "You don't use integers all the time, sometimes you use strings, they're different things." Well, duh?

EDIT: Also, it's discouraged on this site in general to use all caps for emphasis. *phrase* produces an italicized/emphasized form with phrase.

I am using a perfectly sensible notion of "dynamic" (e.g NOT static) when I am talking about "dynamic dispatch".

Registering pointers to new implementations at runtime (adding entries to the dispatch table) Unregistering pointers to old implementations at runtime (removing entries from the dispatch table).

If your dispatch table is immutable (e.g static!), there's nothing dynamic about your dispatch!