state variable chaining

✓ Passing This code compiles and runs correctly.

Code

~import app/data
~app/data:alloc()
| allocated a |> app/data:validate(d: a)
    | validated v |> app/data:process(d: v)
        | processed p |> app/data:finalize(d: p)
            | done _ |> _

input.kz

Imported Files

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

~pub event alloc {}
| allocated *Data<owned>

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

~pub event borrow { other: *Data<owned> }
| borrowed *Data<borrowed>

~proc borrow|zig {
    return .{ .borrowed = other };
}

// Chain of events that all preserve the same state variable M
~pub event validate { d: *Data<M'_> }
| validated *Data<M'_>  // Preserves M

~proc validate|zig {
    return .{ .validated = d };
}

~pub event process { d: *Data<M'_> }
| processed *Data<M'_>  // Preserves M

~proc process|zig {
    return .{ .processed = d };
}

~pub event finalize { d: *Data<M'_> }
| done *Data<M'_>  // Preserves M

~proc finalize|zig {
    return .{ .done = d };
}

data.kz

// Chain of events that all preserve the same state variable M

~pub event validate { data: *Data<M'_> }
| validated *Data<M'_>  // Preserves M

~proc validate|zig {
    return .{ .validated = data };
}

~pub event process { data: *Data<M'_> }
| processed *Data<M'_>  // Preserves M

~proc process|zig {
    return .{ .processed = data };
}

~pub event finalize { data: *Data<M'_> }
| done *Data<M'_>  // Preserves M

~proc finalize|zig {
    return .{ .done = data };
}

processor.kz

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