// Implementation module: a generic value-failable `ufcs` fn + its error set.
#import "modules/std.sx";

LE  :: error { Bad }
Box :: struct ($R: Type) { v: R; }

// Returns `($R, !LE)` — a value-failable. `$R` is inferred from the arg.
get :: ufcs (b: *Box($R)) -> ($R, !LE) { return b.v; }