// Module B aliases the SAME name `Id` to a DIFFERENT type `f64`. A bare `Id` in
// this module resolves to B's `f64` alias, not A's `s32` — each module's alias
// is keyed to its own source, so the two never collide last-wins.
Id :: f64;
b_val :: () -> f64 { x : Id = 2; return x + 0.5; }