// run-pass // As dst-struct.rs, but the unsized field is the only field in the struct. struct Fat { ptr: T } // x is a fat pointer fn foo(x: &Fat<[isize]>) { let y = &x.ptr; assert_eq!(x.ptr.len(), 3); assert_eq!(y[0], 1); assert_eq!(x.ptr[1], 2); } fn foo2(x: &Fat<[T]>) { let y = &x.ptr; let bar = Bar; assert_eq!(x.ptr.len(), 3); assert_eq!(y[0].to_bar(), bar); assert_eq!(x.ptr[1].to_bar(), bar); } #[derive(Copy, Clone, PartialEq, Eq, Debug)] struct Bar; trait ToBar { fn to_bar(&self) -> Bar; } impl ToBar for Bar { fn to_bar(&self) -> Bar { *self } } pub fn main() { // With a vec of ints. let f1 = Fat { ptr: [1, 2, 3] }; foo(&f1); let f2 = &f1; foo(f2); let f3: &Fat<[isize]> = f2; foo(f3); let f4: &Fat<[isize]> = &f1; foo(f4); let f5: &Fat<[isize]> = &Fat { ptr: [1, 2, 3] }; foo(f5); // With a vec of Bars. let bar = Bar; let f1 = Fat { ptr: [bar, bar, bar] }; foo2(&f1); let f2 = &f1; foo2(f2); let f3: &Fat<[Bar]> = f2; foo2(f3); let f4: &Fat<[Bar]> = &f1; foo2(f4); let f5: &Fat<[Bar]> = &Fat { ptr: [bar, bar, bar] }; foo2(f5); // Assignment. let f5: &mut Fat<[isize]> = &mut Fat { ptr: [1, 2, 3] }; f5.ptr[1] = 34; assert_eq!(f5.ptr[0], 1); assert_eq!(f5.ptr[1], 34); assert_eq!(f5.ptr[2], 3); // Zero size vec. let f5: &Fat<[isize]> = &Fat { ptr: [] }; assert!(f5.ptr.is_empty()); let f5: &Fat<[Bar]> = &Fat { ptr: [] }; assert!(f5.ptr.is_empty()); }