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Cloudef | on: Zig – Type Resolution Redesign and Language Changes
I think rust calls them "zero sized types".
tialaramex | parent | next
The ZSTs are unit types. They have one value, which we usually write as just the type name, so e.g.

    struct Goose;

    let x = Goose; // The variable x has type Goose, but also value Goose, the only value of that type
The choice to underscore that Rust's unit types have size zero is to contrast with languages like C or C++ where these types, which don't need representing, must nevertheless take up a whole byte of storage and it's just wasted.

But what we're talking about here are empty types. In Rust we'd write this:

    enum Donkey {}

    // We can't make any variables with the Donkey type, because there are no values of this type and a variable needs a value
mk12 | parent
No, that’s a different thing. “noreturn” is like Rust’s “never” type (spelled as an exclamation mark, !). Also known as an “uninhabited type” in programming language theory.
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Cloudef | root | parent
I see. I can not give more insightful answer here then. From personal experience, I've noticed with 0.16 with the std.Io async stuff that you cannot do:

   io.concurrent(foo, .{});
where foo's return type is `error{foobar}!noreturn`, because the compiler crashes when it tries to use that type as a std.Io.Future(T)'s struct field. Might be related or not.
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