// `xx <pack>` materializes a comptime pack into a runtime slice (issue 0053):
// the explicit pack→slice bridge. With a `[]Any` target each element is boxed
// to `Any`; with a `[]P` target each is `xx`-erased to the protocol `P`. This is
// how you forward a pack to a runtime (`[]Any` / `[]P`) helper.

#import "modules/std.sx";

Show :: protocol { show :: () -> string; }
A :: struct {}
B :: struct { s: string; }
impl Show for A { show :: (self: *A) -> string => "A"; }
impl Show for B { show :: (self: *B) -> string => "B"; }

count_any :: (items: []Any) -> s64 { return items.len; }

show_all :: (items: []Show) -> s64 {
    i := 0;
    while i < items.len { print("{}\n", items[i].show()); i = i + 1; }
    return items.len;
}

// `..$args` pack → []Any via `xx`.
fwd_any :: (..$args) -> s64 { return count_any(xx args); }

// `..xs: Show` pack → []Show via `xx`.
fwd_show :: (..xs: Show) -> s64 { return show_all(xx xs); }

main :: () -> s32 {
    print("any={}\n", fwd_any(1, "hi", 2.5));     // 3
    print("show={}\n", fwd_show(A.{}, B.{ s = "x" }, A.{}));  // A B A, 3
    0;
}