state variable constraint violation

✓ Passing This code compiles and runs correctly.

Code

// PINS: a state VARIABLE constraint is checked against the concrete state.
// `process` accepts `*Data<M'owned|borrowed>`; `gc-alloc` hands back
// `*Data<gc>`, which is neither member, so the call is refused and the
// diagnostic names both the constraint and the state that failed it.
~import app/data
~app/data:gc-alloc(): a |> app/data:process(d: a)

input.kz

Must contain:

error[KORU030]

Flows

flow ~gc-alloc click a branch to expand · @labels scroll to their anchor

gc-alloc

Imported Files

const std = @import("std");
const Data = struct { value: i32 };

~pub tor gc-alloc {} -> *Data<gc>  // GC-managed, NOT owned or borrowed

~proc gc-alloc|zig {
    const allocator = std.heap.page_allocator;
    const d = allocator.create(Data) catch unreachable;
    d.* = Data{ .value = 42 };
    return d;
}

// Generic processor constrained to owned OR borrowed ONLY
~pub tor process { d: *Data<M'owned|borrowed> } -> *Data<M'owned|borrowed>

~proc process|zig {
    return d;
}

data.kz

// Generic processor constrained to owned OR borrowed ONLY

~pub tor process { data: *Data<M'owned|borrowed> } -> *Data<M'owned|borrowed>

~proc process|zig {
    return data;
}

processor.kz

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