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p1necone • yesterday at 10:03 PM • 3 replies • view on HN

Tangential - on the 'use [] instead of <>' advice that you referenced in the post, I wish more languages would experiment with making types first class values that just get passed in regular () braces instead.

With erased static types, you can do arbitrary operations on types-as-values at compile time and just compile the static result into the runtime code, so it doesn't even cost anything at runtime to do this. Generic functions just turn into curried functions with the type params as their first param set.

My wip language uses '()' for 'always explicit params' and '{}' for 'can be implicit params', but both types and values can be passed into both (of course inference only makes sense for statically known types/values, so 'value' params in curly braces must be known at compile time and are treated like singleton types as well as their actual value in runtime code that uses them).


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vinipsmaker • today at 2:51 AM

My own language doesn't try to unify both worlds (values from "type" world and values elsewhere), but my macros can be configured to happen in the type world. From a macro for the type world, you can run normal code to return whatever type you want. It's not the same thing you're talking about, but it's another interesting thing you can do.

tyromaniac • today at 1:11 AM

I believe zig does this

convolvatron • yesterday at 10:45 PM

in logic programming you can just use normal predicates for arbitrary types also.

my understanding is that this makes certain typing decisions undecidable? I agree though the the special parallel type language is a huge amount of added complexity and source of pain.

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