// Generic instantiations memoize on a name built from the argument
// types, so every distinct argument type must spell distinctly. The
// spelling once fell back to a shared catch-all for floats (and
// pointers/slices/arrays), handing `Pair(f64)` the struct layout
// already instantiated for `Pair(f32)` — silent value corruption.

const { assert } = import("test");

fn Pair(T: type) type {
    return struct {
        a: T,
        b: T,
        pub fn sum(self: Self) T { return self.a + self.b; }
    };
}

tfn floatInstantiationsStayDistinct() {
    var p32: Pair(f32) = Pair(f32) { a: 1.5, b: 2.5 };
    var p64: Pair(f64) = Pair(f64) { a: 1.25, b: 2.25 };
    assert((p32.sum() == 4.0) as u8, 1);
    assert((p64.sum() == 3.5) as u8, 1);
}

tfn intAndFloatInstantiationsCoexist() {
    var pi: Pair(u32) = Pair(u32) { a: 3, b: 4 };
    var pf: Pair(f64) = Pair(f64) { a: 0.5, b: 0.25 };
    assert(pi.sum(), 7);
    assert((pf.sum() == 0.75) as u8, 1);
}