// make_enum — the GENERAL comptime enum constructor over declare/define: mint a
// nominal enum from a `[]EnumVariant` VALUE, rather than a hardcoded literal
// (the channel-result constructors hardcode theirs). The variant list is an
// ordinary comptime value, so a builder ASSEMBLES it in a local before minting —
// here `build_level` constructs `vs` (a local array, which could be filled
// conditionally / in a loop), then mints `Level` from it.
//
// This exercises `define` decoding a value-arg SLICE (`decodeVariantElements`'s
// slice-fat-pointer branch), as opposed to the inline `.[ … ]` array the
// 0614–0618 examples pass directly into `.enum(...)`.
#import "modules/std.sx";
#import "modules/std/meta.sx";

build_level :: () -> Type {
    // The variant list lives in a local (not inlined into `define`): a non-
    // generic `() -> Type` builder has its whole body comptime-evaluated, so
    // `vs` is in scope when `make_enum` mints from it.
    vs := EnumVariant.[
        EnumVariant.{ name = "info",  payload = void },
        EnumVariant.{ name = "warn",  payload = void },
        EnumVariant.{ name = "fatal", payload = i64 },   // carries an exit code
    ];
    return make_enum("Level", vs);
}

Level :: build_level();

show :: (l: Level) {
    if l == {
        case .info:      { print("info\n"); }
        case .warn:      { print("warn\n"); }
        case .fatal: (c) { print("fatal code={}\n", c); }
    }
}

main :: () -> i32 {
    show(.info);
    show(.warn);
    show(.fatal(70));
    return 0;
}